Kapitel 7 abgeschlossen.

2026-08-16 00:29:01 +02:00
parent da8d2bb1da
commit f9e398b225
47 changed files with 2636 additions and 107 deletions
@@ -140,10 +140,12 @@ public static class AppBootstrapper
        // ── Services ──────────────────────────────────────────────────────────
        services.AddSingleton<GradingService>();
        services.AddSingleton<SchoolYearService>();
+        services.AddSingleton<GroupRolloverService>();
        services.AddSingleton<PublicHolidayService>();
        services.AddSingleton(_ => new SchoolCalendarSettingsService(appData));
        services.AddSingleton(_ => new PeriodScheduleService(appData));
        services.AddSingleton(_ => new WorkloadSettingsService(appData));
+        services.AddSingleton(_ => new LetterTemplateService(appData));

        // ── Sync (optional – nur wenn Server konfiguriert) ────────────────────
        services.AddSingleton(_ => new EventQueue(queuePath));
@@ -37,6 +37,7 @@ public partial class GradeOverviewTabViewModel : ObservableObject
    [ObservableProperty] private bool _showAsPoints = true;
    [ObservableProperty] private GradeOverviewRow? _selectedRow;
    [ObservableProperty] private int _rebuildColumnsSignal;
+    [ObservableProperty] private bool _isReadOnly;

    public bool CanTogglePointsView => _gradingSystem == GradingSystem.Points0To15;

@@ -64,13 +65,14 @@ public partial class GradeOverviewTabViewModel : ObservableObject
    }

    public void Initialize(Guid groupId, GradingSystem gradingSystem, GroupType groupType,
-        string groupLabel, string schoolYear)
+        string groupLabel, string schoolYear, bool isReadOnly = false)
    {
        _groupId = groupId;
        _gradingSystem = gradingSystem;
        _groupType = groupType;
        _groupLabel = groupLabel;
        _schoolYear = schoolYear;
+        IsReadOnly = isReadOnly;
        ShowAsPoints = gradingSystem == GradingSystem.Points0To15;
        OnPropertyChanged(nameof(CanTogglePointsView));
        Recompute();
@@ -0,0 +1,164 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using LehrerApp.Core.Interfaces;
+using LehrerApp.Core.Models;
+using LehrerApp.Core.Services;
+using System.Collections.ObjectModel;
+
+namespace LehrerApp.Desktop.ViewModels.Groups;
+
+public partial class GroupRolloverDialogViewModel : ObservableObject
+{
+    private readonly LearningGroup _source;
+    private readonly GroupRolloverService _rollover;
+    private readonly SchoolYearService _schoolYears;
+
+    [ObservableProperty] private string _name;
+    [ObservableProperty] private string _targetSchoolYear;
+    [ObservableProperty] private int _gradeLevel;
+    [ObservableProperty] private bool _copyGradingScheme;
+    [ObservableProperty] private bool _archiveSource = true;
+    [ObservableProperty] private string _nameError = "";
+    [ObservableProperty] private string _schoolYearError = "";
+    [ObservableProperty] private string _selectionError = "";
+    [ObservableProperty] private string _generalError = "";
+
+    public string SourceSummary => $"{_source.Name} · {_source.SchoolYear} · Stufe {_source.GradeLevel}";
+    public bool HasGradingScheme { get; }
+    public int SelectedCount => Students.Count(s => s.IsSelected);
+    public string SelectedCountText => $"{SelectedCount} von {Students.Count} Schülern ausgewählt";
+    public ObservableCollection<GroupRolloverStudentItem> Students { get; } = [];
+    public LearningGroup? Result { get; private set; }
+
+    public GroupRolloverDialogViewModel(LearningGroup source,
+        IStudentRepository students, IGroupMembershipRepository memberships,
+        IGradingSchemeRepository gradingSchemes, SchoolYearService schoolYears,
+        GroupRolloverService rollover)
+    {
+        _source = source;
+        _rollover = rollover;
+        _schoolYears = schoolYears;
+        _name = source.Name;
+        _targetSchoolYear = NextSchoolYear(source.SchoolYear, schoolYears);
+        _gradeLevel = Math.Min(13, source.GradeLevel + 1);
+        HasGradingScheme = gradingSchemes.GetByGroup(source.Id) is not null;
+        _copyGradingScheme = HasGradingScheme;
+
+        var sourceEnd = schoolYears.SchoolYearEnd(source.SchoolYear);
+        foreach (var membership in memberships.GetByGroup(source.Id)
+                     .Select(m => (Membership: m, Student: students.GetById(m.StudentId)))
+                     .Where(x => x.Student is not null)
+                     .OrderBy(x => x.Student!.LastName).ThenBy(x => x.Student!.FirstName))
+        {
+            var canSelect = membership.Student!.IsActive;
+            var isPreselected = canSelect
+                                && GroupMembershipService.IsActiveOn(membership.Membership, sourceEnd);
+            var item = new GroupRolloverStudentItem(
+                membership.Student, membership.Membership, isPreselected, canSelect);
+            item.PropertyChanged += (_, e) =>
+            {
+                if (e.PropertyName != nameof(GroupRolloverStudentItem.IsSelected)) return;
+                SelectionError = "";
+                OnPropertyChanged(nameof(SelectedCount));
+                OnPropertyChanged(nameof(SelectedCountText));
+            };
+            Students.Add(item);
+        }
+    }
+
+    [RelayCommand]
+    private void Save()
+    {
+        NameError = "";
+        SchoolYearError = "";
+        SelectionError = "";
+        GeneralError = "";
+        var valid = true;
+
+        if (string.IsNullOrWhiteSpace(Name))
+        {
+            NameError = "Gruppenname erforderlich.";
+            valid = false;
+        }
+        try
+        {
+            var targetText = TargetSchoolYear.Trim();
+            var targetStart = _schoolYears.SchoolYearStart(targetText);
+            if (targetText != _schoolYears.FormatSchoolYear(targetStart.Year))
+            {
+                SchoolYearError = "Format JJJJ/JJ, z.B. 2027/28.";
+                valid = false;
+            }
+            else if (targetStart <= _schoolYears.SchoolYearStart(_source.SchoolYear))
+            {
+                SchoolYearError = "Das Zielschuljahr muss nach dem bisherigen liegen.";
+                valid = false;
+            }
+        }
+        catch (Exception ex) when (ex is FormatException or ArgumentOutOfRangeException or IndexOutOfRangeException)
+        {
+            SchoolYearError = "Format JJJJ/JJ, z.B. 2027/28.";
+            valid = false;
+        }
+        if (SelectedCount == 0)
+        {
+            SelectionError = "Bitte mindestens einen Schüler auswählen.";
+            valid = false;
+        }
+        if (!valid) return;
+
+        try
+        {
+            Result = _rollover.RollOver(_source, new GroupRolloverRequest(
+                Name, TargetSchoolYear.Trim(), GradeLevel,
+                Students.Where(s => s.IsSelected).Select(s => s.MembershipId).ToList(),
+                CopyGradingScheme, ArchiveSource));
+        }
+        catch (Exception ex) when (ex is InvalidOperationException or FormatException or ArgumentOutOfRangeException)
+        {
+            GeneralError = ex.Message;
+        }
+    }
+
+    private static string NextSchoolYear(string source, SchoolYearService schoolYears)
+    {
+        var start = schoolYears.SchoolYearStart(source);
+        return schoolYears.FormatSchoolYear(start.Year + 1);
+    }
+}
+
+public partial class GroupRolloverStudentItem : ObservableObject
+{
+    [ObservableProperty] private bool _isSelected;
+
+    public Guid MembershipId { get; }
+    public string FullName { get; }
+    public string NiveauText { get; }
+    public string MembershipStatus { get; }
+    public bool CanSelect { get; }
+
+    public GroupRolloverStudentItem(Student student, GroupMembership membership,
+        bool isSelected, bool canSelect)
+    {
+        MembershipId = membership.Id;
+        FullName = student.FullName;
+        NiveauText = membership.Niveau?.ToString() ?? "–";
+        CanSelect = canSelect;
+        _isSelected = isSelected;
+        MembershipStatus = BuildStatus(student, membership, isSelected);
+    }
+
+    partial void OnIsSelectedChanged(bool value)
+    {
+        if (!CanSelect && value) IsSelected = false;
+    }
+
+    private static string BuildStatus(Student student, GroupMembership membership, bool isPreselected)
+    {
+        if (!student.IsActive) return "Schüler inaktiv · nicht übernehmbar";
+        if (isPreselected) return "Bis Schuljahresende aktiv · vorausgewählt";
+        if (membership.LeftAt is { } leftAt) return $"Ausgetreten am {leftAt:dd.MM.yyyy} · nicht vorausgewählt";
+        if (membership.Period == MembershipPeriod.H1Only) return "Nur 1. Halbjahr · nicht vorausgewählt";
+        return "Am Schuljahresende nicht aktiv · nicht vorausgewählt";
+    }
+}
@@ -3,6 +3,7 @@ using CommunityToolkit.Mvvm.Input;
 using LehrerApp.Core.Interfaces;
 using LehrerApp.Core.Models;
 using LehrerApp.Core.Services;
+using LehrerApp.Desktop.ViewModels.Students;
 using System.Collections.ObjectModel;

 namespace LehrerApp.Desktop.ViewModels.Groups;
@@ -17,6 +18,7 @@ public partial class GroupListViewModel : ObservableObject
    public Action<Guid, int>? OnNavigateToDetail { get; set; }
    public Func<Task>? OnAddGroup { get; set; }
    public Func<Guid, Task>? OnEditGroup { get; set; }
+    public Func<Guid, Task<Guid?>>? OnRollOverGroup { get; set; }
    public Func<GroupListItem, Task<bool>>? OnConfirmDelete { get; set; }

    [ObservableProperty] private string _selectedSchoolYear = "";
@@ -53,6 +55,7 @@ public partial class GroupListViewModel : ObservableObject
        OnPropertyChanged(nameof(SelectedGroupSubtitle));
        NavigateToSectionCommand.NotifyCanExecuteChanged();
        EditGroupCommand.NotifyCanExecuteChanged();
+        RollOverGroupCommand.NotifyCanExecuteChanged();
        ToggleArchiveCommand.NotifyCanExecuteChanged();
        DeleteGroupCommand.NotifyCanExecuteChanged();
    }
@@ -85,7 +88,7 @@ public partial class GroupListViewModel : ObservableObject
    }
    [RelayCommand] private void Refresh()   => LoadGroups();

-    [RelayCommand(CanExecute = nameof(HasSelectedGroup))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedGroup))]
    private async Task EditGroup()
    {
        if (SelectedGroup is null || OnEditGroup is null) return;
@@ -95,6 +98,20 @@ public partial class GroupListViewModel : ObservableObject
        SelectedGroup = Groups.FirstOrDefault(g => g.Id == id);
    }

+    [RelayCommand(CanExecute = nameof(HasSelectedGroup))]
+    private async Task RollOverGroup()
+    {
+        if (SelectedGroup is null || OnRollOverGroup is null) return;
+        var targetId = await OnRollOverGroup(SelectedGroup.Id);
+        if (targetId is null) return;
+        var target = _groups.GetById(targetId.Value);
+        if (target is null) return;
+        if (!SchoolYears.Contains(target.SchoolYear)) SchoolYears.Insert(0, target.SchoolYear);
+        SelectedSchoolYear = target.SchoolYear;
+        LoadGroups();
+        SelectedGroup = Groups.FirstOrDefault(g => g.Id == target.Id);
+    }
+
    [RelayCommand(CanExecute = nameof(HasSelectedGroup))]
    private void ToggleArchive()
    {
@@ -106,7 +123,7 @@ public partial class GroupListViewModel : ObservableObject
        LoadGroups();
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedGroup))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedGroup))]
    private async Task DeleteGroup()
    {
        if (SelectedGroup is null || OnConfirmDelete is null) return;
@@ -124,6 +141,7 @@ public partial class GroupListViewModel : ObservableObject
    }

    private bool HasSelectedGroup() => SelectedGroup is not null;
+    private bool CanEditSelectedGroup() => SelectedGroup?.IsActive == true;
 }

 public class GroupListItem
@@ -175,9 +193,17 @@ public partial class GroupDetailViewModel : ObservableObject
    // bevor LoadGroup() läuft (siehe MainWindowViewModel.NavigateToGroupDetail), Group ist dann
    // kurzzeitig null — ein verschachtelter Pfad würde dafür jedes Mal einen Binding-Fehler loggen.
    public bool IsDifferentiated => Group?.IsDifferentiated ?? false;
+    public bool IsReadOnly => Group is { IsActive: false };
+    public bool IsEditable => Group is { IsActive: true };
    public string SubjectName { get; private set; } = "";

-    partial void OnGroupChanged(LearningGroup? value) => OnPropertyChanged(nameof(IsDifferentiated));
+    partial void OnGroupChanged(LearningGroup? value)
+    {
+        OnPropertyChanged(nameof(IsDifferentiated));
+        OnPropertyChanged(nameof(IsReadOnly));
+        OnPropertyChanged(nameof(IsEditable));
+        NotifyWriteCommands();
+    }
    partial void OnShowFormerStudentsChanged(bool value) => LoadStudents();

    public ObservableCollection<StudentSummary> Students { get; } = [];
@@ -194,6 +220,7 @@ public partial class GroupDetailViewModel : ObservableObject
    public Func<ExamSummary, Task<bool>>? OnConfirmDeleteExam { get; set; }
    public Func<Exam, Task>? OnGradeExam { get; set; }
    public Func<Exam, Task>? OnEvaluateExam { get; set; }
+    public Func<Task<bool>>? OnConfirmReactivate { get; set; }

    public GroupDetailViewModel(IGroupRepository groups, IStudentRepository students,
        IGroupMembershipRepository memberships, ISubjectRepository subjects,
@@ -221,9 +248,9 @@ public partial class GroupDetailViewModel : ObservableObject
                        $"Stufe {Group.GradeLevel} · Noten {(Group.GradingSystem == GradingSystem.Grades1To6 ? "1–6" : "0–15")}";
        LoadStudents();
        ReloadExams();
-        ParticipationTab.Initialize(Group.Id, Group.SchoolYear);
-        GradeOverviewTab.Initialize(Group.Id, Group.GradingSystem, Group.Type, GroupTitle, Group.SchoolYear);
-        PlanningTab.Initialize(Group.Id);
+        ParticipationTab.Initialize(Group.Id, Group.SchoolYear, IsReadOnly);
+        GradeOverviewTab.Initialize(Group.Id, Group.GradingSystem, Group.Type, GroupTitle, Group.SchoolYear, IsReadOnly);
+        PlanningTab.Initialize(Group.Id, IsReadOnly);
    }

    private void ReloadExams()
@@ -247,7 +274,11 @@ public partial class GroupDetailViewModel : ObservableObject
        {
            memberships.TryGetValue(s.Id, out var membership);
            if (membership is null) continue;
-            var summary = new StudentSummary(s, membership, today) { OnChanged = SaveStudentNiveau };
+            var summary = new StudentSummary(s, membership, today)
+            {
+                OnChanged = SaveStudentNiveau,
+                CanEdit = IsEditable,
+            };
            if (summary.IsFormer && !ShowFormerStudents) continue;
            Students.Add(summary);
        }
@@ -255,14 +286,14 @@ public partial class GroupDetailViewModel : ObservableObject

    private void SaveStudentNiveau(StudentSummary summary)
    {
-        if (Group is null) return;
+        if (!IsEditable || Group is null) return;
        var membership = _memberships.GetByStudentAndGroup(summary.Id, Group.Id);
        if (membership is null) return;
        membership.Niveau = summary.Niveau;
        _memberships.Save(membership);
    }

-    [RelayCommand]
+    [RelayCommand(CanExecute = nameof(IsEditableGroup))]
    private async Task AddStudent()
    {
        if (OnAddStudent is null) return;
@@ -274,7 +305,7 @@ public partial class GroupDetailViewModel : ObservableObject
        }
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedStudent))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedStudent))]
    private async Task WithdrawStudent()
    {
        if (SelectedStudent is null || OnWithdrawStudent is null) return;
@@ -284,7 +315,7 @@ public partial class GroupDetailViewModel : ObservableObject
        ParticipationTab.RefreshCurrentGrid();
    }

-    [RelayCommand(CanExecute = nameof(CanReinstateSelectedStudent))]
+    [RelayCommand(CanExecute = nameof(CanEditAndReinstateSelectedStudent))]
    private void ReinstateStudent()
    {
        if (Group is null || SelectedStudent is null) return;
@@ -303,10 +334,10 @@ public partial class GroupDetailViewModel : ObservableObject
        ReinstateStudentCommand.NotifyCanExecuteChanged();
    }

-    private bool HasSelectedStudent() => SelectedStudent is not null;
-    private bool CanReinstateSelectedStudent() => SelectedStudent?.HasExitDate == true;
+    private bool CanEditSelectedStudent() => IsEditable && SelectedStudent is not null;
+    private bool CanEditAndReinstateSelectedStudent() => IsEditable && SelectedStudent?.HasExitDate == true;

-    [RelayCommand]
+    [RelayCommand(CanExecute = nameof(IsEditableGroup))]
    private async Task AddExam()
    {
        if (Group is null || OnAddExam is null) return;
@@ -314,7 +345,7 @@ public partial class GroupDetailViewModel : ObservableObject
        if (saved) ReloadExams();
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private async Task EditExam()
    {
        if (SelectedExam is null || OnEditExam is null) return;
@@ -329,7 +360,7 @@ public partial class GroupDetailViewModel : ObservableObject
        }
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private async Task GradeExam()
    {
        if (SelectedExam is null || OnGradeExam is null) return;
@@ -338,7 +369,7 @@ public partial class GroupDetailViewModel : ObservableObject
        await OnGradeExam(exam);
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private async Task EvaluateExam()
    {
        if (SelectedExam is null || OnEvaluateExam is null) return;
@@ -347,7 +378,7 @@ public partial class GroupDetailViewModel : ObservableObject
        await OnEvaluateExam(exam);
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private async Task DuplicateExam()
    {
        if (SelectedExam is null || OnDuplicateExam is null) return;
@@ -357,7 +388,7 @@ public partial class GroupDetailViewModel : ObservableObject
        if (saved) ReloadExams();
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private async Task DeleteExam()
    {
        if (SelectedExam is null || OnConfirmDeleteExam is null) return;
@@ -368,7 +399,7 @@ public partial class GroupDetailViewModel : ObservableObject
        ReloadExams();
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private void AdvanceExamStatus()
    {
        if (SelectedExam is null) return;
@@ -381,7 +412,7 @@ public partial class GroupDetailViewModel : ObservableObject
        });
    }

-    [RelayCommand(CanExecute = nameof(HasSelectedExam))]
+    [RelayCommand(CanExecute = nameof(CanEditSelectedExam))]
    private void SetExamStatus(ExamStatus status)
    {
        if (SelectedExam is null) return;
@@ -409,7 +440,35 @@ public partial class GroupDetailViewModel : ObservableObject
        SetExamStatusCommand.NotifyCanExecuteChanged();
    }

-    private bool HasSelectedExam() => SelectedExam is not null;
+    private bool CanEditSelectedExam() => IsEditable && SelectedExam is not null;
+    private bool IsEditableGroup() => IsEditable;
+
+    [RelayCommand(CanExecute = nameof(IsReadOnlyGroup))]
+    private async Task ReactivateGroup()
+    {
+        if (Group is null || OnConfirmReactivate is null || !await OnConfirmReactivate()) return;
+        Group.IsActive = true;
+        _groups.Save(Group);
+        LoadGroup(Group.Id);
+    }
+
+    private bool IsReadOnlyGroup() => IsReadOnly;
+
+    private void NotifyWriteCommands()
+    {
+        AddStudentCommand.NotifyCanExecuteChanged();
+        WithdrawStudentCommand.NotifyCanExecuteChanged();
+        ReinstateStudentCommand.NotifyCanExecuteChanged();
+        AddExamCommand.NotifyCanExecuteChanged();
+        EditExamCommand.NotifyCanExecuteChanged();
+        GradeExamCommand.NotifyCanExecuteChanged();
+        EvaluateExamCommand.NotifyCanExecuteChanged();
+        DuplicateExamCommand.NotifyCanExecuteChanged();
+        DeleteExamCommand.NotifyCanExecuteChanged();
+        AdvanceExamStatusCommand.NotifyCanExecuteChanged();
+        SetExamStatusCommand.NotifyCanExecuteChanged();
+        ReactivateGroupCommand.NotifyCanExecuteChanged();
+    }

    [RelayCommand] private void Refresh()  { if (Group is not null) LoadGroup(Group.Id); }
 }
@@ -448,6 +507,9 @@ public partial class StudentSummary : ObservableObject
    public bool HasExitDate { get; }
    public string MembershipStatus { get; }
    public string WithdrawActionLabel => HasExitDate ? "Austrittsdatum ändern" : "Austragen";
+    public string AvatarLabel { get; }
+    public string AvatarColor { get; }
+    public string AvatarTooltip { get; }

    [ObservableProperty] private Niveau? _niveau;

@@ -458,11 +520,15 @@ public partial class StudentSummary : ObservableObject
    }

    public Action<StudentSummary>? OnChanged { get; set; }
+    public bool CanEdit { get; init; } = true;

    public StudentSummary(Core.Models.Student s, GroupMembership? membership, DateOnly? today = null)
    {
        Id     = s.Id;
        FullName = s.FullName;
+        AvatarLabel = GenderAvatarDisplay.Label(s.Gender);
+        AvatarColor = GenderAvatarDisplay.Color(s.Gender);
+        AvatarTooltip = GenderAvatarDisplay.Tooltip(s.Gender);
        PeriodLabel = membership is null ? "" : BuildPeriodLabel(membership);
        HasExitDate = membership?.LeftAt.HasValue == true;
        IsFormer = membership?.LeftAt is { } leftAt
@@ -37,6 +37,7 @@ public partial class ParticipationTabViewModel : ObservableObject
    [ObservableProperty] private bool   _hasCompetencyCatalog;
    [ObservableProperty] private bool   _studentCompetencyRatingsVisible;
    [ObservableProperty] private int    _rebuildColumnsSignal;
+    [ObservableProperty] private bool   _isReadOnly;

    public string SelectedSessionDisplay => SelectedSession?.Display ?? "";
    public List<string> ActiveCompetencyCodes { get; private set; } = [];
@@ -67,10 +68,11 @@ public partial class ParticipationTabViewModel : ObservableObject
        _competencyDomains = competencyDomains;
    }

-    public void Initialize(Guid groupId, string schoolYear)
+    public void Initialize(Guid groupId, string schoolYear, bool isReadOnly = false)
    {
        _groupId    = groupId;
        _schoolYear = schoolYear;
+        IsReadOnly  = isReadOnly;

        var group   = _groups.GetById(groupId);
        _subjectId  = group?.SubjectId;
@@ -160,6 +162,7 @@ public partial class ParticipationTabViewModel : ObservableObject

    private void SaveRating(Guid sessionId, Guid studentId, string key, int? value)
    {
+        if (IsReadOnly) return;
        var entry = _entries.GetBySessionAndStudent(sessionId, studentId)
                      ?? new ParticipationEntry
                      {
@@ -187,6 +190,7 @@ public partial class ParticipationTabViewModel : ObservableObject

    private void SaveHomework(Guid sessionId, Guid studentId, HomeworkStatus? value)
    {
+        if (IsReadOnly) return;
        var entry = _entries.GetBySessionAndStudent(sessionId, studentId)
                    ?? new ParticipationEntry { SessionId = sessionId, StudentId = studentId };
        entry.Homework = value;
@@ -196,6 +200,7 @@ public partial class ParticipationTabViewModel : ObservableObject

    private void SaveAttendance(Guid sessionId, Guid studentId, AttendanceStatus? value)
    {
+        if (IsReadOnly) return;
        var entry = _entries.GetBySessionAndStudent(sessionId, studentId)
                    ?? new ParticipationEntry { SessionId = sessionId, StudentId = studentId };
        entry.Attendance = value;
@@ -39,6 +39,7 @@ public partial class PlanningTabViewModel : ObservableObject

    [ObservableProperty] private UnitSummary? _selectedUnit;
    [ObservableProperty] private LessonSummary? _selectedLesson;
+    [ObservableProperty] private bool _isReadOnly;

    // Eigene Property statt "SelectedUnit.Title" im Binding-Pfad: SelectedUnit ist zwischen
    // Gruppenwechsel/Laden kurzzeitig null — ein verschachtelter Pfad würde dafür jedes Mal
@@ -74,9 +75,10 @@ public partial class PlanningTabViewModel : ObservableObject
        _subjects = subjects; _competencyDomains = competencyDomains;
    }

-    public void Initialize(Guid groupId)
+    public void Initialize(Guid groupId, bool isReadOnly = false)
    {
        _groupId = groupId;
+        IsReadOnly = isReadOnly;
        var group = _groups.GetById(groupId);
        SubjectId  = group?.SubjectId;
        GradeLevel = group?.GradeLevel ?? 0;
@@ -64,7 +64,7 @@ public partial class MainWindowViewModel : ObservableObject
        {
            NavItem.Dashboard => GetDashboard(),
            NavItem.Groups    => _services.GetRequiredService<GroupListViewModel>(),
-            NavItem.Students  => _services.GetRequiredService<StudentListViewModel>(),
+            NavItem.Students  => GetStudents(),
            NavItem.Exams     => new PlaceholderViewModel { Title = "Klausuren", Icon = "📝" },
            NavItem.Planner   => GetTimetable(),
            NavItem.Workload  => GetWorkload(),
@@ -80,6 +80,14 @@ public partial class MainWindowViewModel : ObservableObject
        return dashboard;
    }

+    private StudentListViewModel GetStudents()
+    {
+        var students = _services.GetRequiredService<StudentListViewModel>();
+        students.SelectedStudent = null;
+        students.LoadStudents();
+        return students;
+    }
+
    private TimetableViewModel GetTimetable()
    {
        var timetable = _services.GetRequiredService<TimetableViewModel>();
@@ -120,9 +128,12 @@ public partial class MainWindowViewModel : ObservableObject
    {
        ActiveNavItem = NavItem.Students;
        var vm = _services.GetRequiredService<StudentDetailViewModel>();
+        vm.OnReturnToStudentList = NavigateToStudents;
        vm.LoadStudent(studentId);
        CurrentPage = vm;
    }
+
+    public void NavigateToStudents() => NavigateTo(NavItem.Students);
 }

 public enum NavItem { Dashboard, Groups, Students, Exams, Planner, Workload, Settings }
@@ -29,6 +29,7 @@ public partial class SettingsViewModel : ObservableObject
    private readonly IDocumentationRepository _documentation;
    private readonly IStudentRepository _students;
    private readonly IShorthandCodeRepository _shorthandCodes;
+    private readonly LetterTemplateService _letterTemplates;

    [ObservableProperty] private int _activeTabIndex;

@@ -67,6 +68,13 @@ public partial class SettingsViewModel : ObservableObject
    public List<string> GradingSystemOptions { get; } = ["Noten 1–6", "Punkte 0–15"];
    public ObservableCollection<GradingKeyTemplateEditItem> GradingKeyTemplateList { get; } = [];

+    // ── Word-Briefvorlagen (7.1.4 / 11.5) ───────────────────────────────────
+
+    [ObservableProperty] private string _letterTemplateStatus = "";
+    public ObservableCollection<LetterTemplateListItem> LetterTemplateList { get; } = [];
+    public IReadOnlyList<LetterPlaceholder> SupportedLetterPlaceholders =>
+        LetterTemplateService.SupportedPlaceholders;
+
    // ── Gewichtungsschema-Voreinstellungen (2.3.3) ───────────────────────────

    [ObservableProperty] private GradingSchemeEditItem _classScheme = null!;
@@ -160,7 +168,7 @@ public partial class SettingsViewModel : ObservableObject
        IDocumentationRepository documentation, IStudentRepository students,
        IShorthandCodeRepository shorthandCodes, ISchoolHolidayRepository schoolHolidays,
        SchoolCalendarSettingsService calendarSettings, PeriodScheduleService periodSchedule,
-        ISupervisionDutyRepository supervisionDuties)
+        ISupervisionDutyRepository supervisionDuties, LetterTemplateService letterTemplates)
    {
        _subjects   = subjects;
        _domainRepo = domainRepo;
@@ -179,6 +187,7 @@ public partial class SettingsViewModel : ObservableObject
        _calendarSettings = calendarSettings;
        _periodSchedule = periodSchedule;
        _supervisionDuties = supervisionDuties;
+        _letterTemplates = letterTemplates;
        LoadSubjects();
        LoadShorthandCodes();
        LoadGradingKeyTemplates();
@@ -193,6 +202,55 @@ public partial class SettingsViewModel : ObservableObject
        LoadSchoolHolidays();
        LoadPeriodTimes();
        LoadSupervisionDuties();
+        LoadLetterTemplates();
+    }
+
+    // ── Word-Briefvorlagen: Import und Validierung ──────────────────────────
+
+    private void LoadLetterTemplates()
+    {
+        LetterTemplateList.Clear();
+        foreach (var template in _letterTemplates.GetTemplates())
+            LetterTemplateList.Add(new LetterTemplateListItem(template, _letterTemplates.Validate(template)));
+    }
+
+    public void ImportLetterTemplate(string path)
+    {
+        LetterTemplateStatus = "";
+        try
+        {
+            var template = _letterTemplates.Import(path);
+            var validation = _letterTemplates.Validate(template);
+            LoadLetterTemplates();
+            LetterTemplateStatus = validation.Issues.Count == 0
+                ? "Vorlage importiert und ohne Auffälligkeiten geprüft."
+                : $"Vorlage importiert. Die Prüfung meldet {validation.Issues.Count} Hinweis(e).";
+        }
+        catch (Exception ex) when (ex is IOException or InvalidDataException or UnauthorizedAccessException)
+        {
+            LetterTemplateStatus = $"Import fehlgeschlagen: {ex.Message}";
+        }
+    }
+
+    [RelayCommand]
+    private void ValidateLetterTemplate(LetterTemplateListItem? item)
+    {
+        if (item is null) return;
+        var index = LetterTemplateList.IndexOf(item);
+        var refreshed = new LetterTemplateListItem(item.Model, _letterTemplates.Validate(item.Model));
+        if (index >= 0) LetterTemplateList[index] = refreshed;
+        LetterTemplateStatus = refreshed.Validation.Issues.Count == 0
+            ? $"„{item.Name}“ ist ohne Auffälligkeiten."
+            : $"„{item.Name}“: {refreshed.Validation.Issues.Count} Hinweis(e).";
+    }
+
+    [RelayCommand]
+    private void DeleteLetterTemplate(LetterTemplateListItem? item)
+    {
+        if (item is null) return;
+        _letterTemplates.Delete(item.Id);
+        LetterTemplateList.Remove(item);
+        LetterTemplateStatus = "Vorlage gelöscht.";
    }

    // ── Aufsichten: Laden / Hinzufügen / Löschen ─────────────────────────────
@@ -929,6 +987,45 @@ public class BackupListItem(BackupInfo info)
    public string Display { get; } = $"{info.CreatedAt:dd.MM.yyyy HH:mm} · {info.SizeBytes / 1024.0:0} KB";
 }

+public sealed class LetterTemplateListItem
+{
+    public LetterTemplateInfo Model { get; }
+    public TemplateValidationResult Validation { get; }
+    public Guid Id => Model.Id;
+    public string Name => Model.Name;
+    public string OriginalFileName => Model.OriginalFileName;
+    public bool HasIssues => Validation.Issues.Count > 0;
+    public bool HasNoIssues => !HasIssues;
+    public string ValidationSummary => HasNoIssues
+        ? $"{Validation.Tags.Count} Feld(er) · keine Auffälligkeiten"
+        : $"{Validation.Tags.Count} Feld(er) · {Validation.Issues.Count} Hinweis(e)";
+    public ObservableCollection<LetterTemplateIssueItem> Issues { get; }
+
+    public LetterTemplateListItem(LetterTemplateInfo model, TemplateValidationResult validation)
+    {
+        Model = model;
+        Validation = validation;
+        Issues = new(validation.Issues.Select(i => new LetterTemplateIssueItem(i)));
+    }
+}
+
+public sealed class LetterTemplateIssueItem(TemplateValidationIssue issue)
+{
+    public string Icon => issue.Severity switch
+    {
+        TemplateIssueSeverity.Error => "⛔",
+        TemplateIssueSeverity.StrongWarning => "⚠",
+        _ => "ⓘ",
+    };
+    public string Message => issue.Message;
+    public string Color => issue.Severity switch
+    {
+        TemplateIssueSeverity.Error => "#DC2626",
+        TemplateIssueSeverity.StrongWarning => "#D97706",
+        _ => "#6B7280",
+    };
+}
+
 public class ExpiredDocumentItem(Documentation d, string studentName)
 {
    public Guid Id { get; } = d.Id;
@@ -0,0 +1,182 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using LehrerApp.Core.Interfaces;
+using LehrerApp.Core.Models;
+using LehrerApp.Core.Services;
+using System.Collections.ObjectModel;
+using System.Globalization;
+
+namespace LehrerApp.Desktop.ViewModels.Students;
+
+public partial class CreateLetterDialogViewModel : ObservableObject
+{
+    private readonly Student _student;
+    private readonly LetterTemplateService _templates;
+
+    [ObservableProperty] private LetterTemplateChoice? _selectedTemplate;
+    [ObservableProperty] private LetterContactChoice? _selectedContact;
+    [ObservableProperty] private LetterGroupChoice? _selectedGroup;
+    [ObservableProperty] private DateTimeOffset? _letterDate = DateTimeOffset.Now;
+    [ObservableProperty] private string _generationError = "";
+    [ObservableProperty] private bool _canGenerate;
+
+    public string StudentName => _student.FullName;
+    public ObservableCollection<LetterTemplateChoice> Templates { get; } = [];
+    public ObservableCollection<LetterContactChoice> Contacts { get; } = [];
+    public ObservableCollection<LetterGroupChoice> Groups { get; } = [];
+    public ObservableCollection<LetterGenerationIssue> Issues { get; } = [];
+    public bool HasIssues => Issues.Count > 0;
+    public bool HasNoTemplates => Templates.Count == 0;
+    public bool HasNoContacts => Contacts.Count == 0;
+    public string SuggestedFileName => SanitizeFileName(
+        $"{SelectedTemplate?.Name ?? "Elternbrief"}_{_student.LastName}_{_student.FirstName}.docx");
+
+    public CreateLetterDialogViewModel(Student student, LetterTemplateService templates,
+        IGroupMembershipRepository memberships, IGroupRepository groups)
+    {
+        _student = student;
+        _templates = templates;
+
+        foreach (var template in templates.GetTemplates())
+            Templates.Add(new LetterTemplateChoice(template));
+        foreach (var contact in student.Contacts.Where(c => !c.InvalidSince.HasValue).OrderBy(c => c.Name))
+            Contacts.Add(new LetterContactChoice(contact));
+        foreach (var membership in memberships.GetByStudent(student.Id))
+        {
+            var group = groups.GetById(membership.GroupId);
+            if (group is not null) Groups.Add(new LetterGroupChoice(group));
+        }
+
+        SelectedTemplate = Templates.FirstOrDefault();
+        SelectedContact = Contacts.FirstOrDefault();
+        SelectedGroup = Groups.FirstOrDefault();
+        RefreshValidation();
+    }
+
+    partial void OnSelectedTemplateChanged(LetterTemplateChoice? value)
+    {
+        OnPropertyChanged(nameof(SuggestedFileName));
+        RefreshValidation();
+    }
+    partial void OnSelectedContactChanged(LetterContactChoice? value) => RefreshValidation();
+    partial void OnSelectedGroupChanged(LetterGroupChoice? value) => RefreshValidation();
+    partial void OnLetterDateChanged(DateTimeOffset? value) => RefreshValidation();
+
+    public bool Generate(string outputPath)
+    {
+        RefreshValidation();
+        if (!CanGenerate || SelectedTemplate is null) return false;
+        GenerationError = "";
+        try
+        {
+            _templates.Generate(_templates.GetTemplatePath(SelectedTemplate.Model), outputPath, BuildValues());
+            return true;
+        }
+        catch (Exception ex) when (ex is IOException or InvalidDataException or UnauthorizedAccessException)
+        {
+            GenerationError = $"Der Brief konnte nicht erzeugt werden: {ex.Message}";
+            return false;
+        }
+    }
+
+    private void RefreshValidation()
+    {
+        Issues.Clear();
+        GenerationError = "";
+
+        if (SelectedTemplate is null)
+            Issues.Add(new("Bitte zuerst in den Einstellungen eine DOCX-Briefvorlage importieren.", true));
+        if (SelectedContact is null)
+            Issues.Add(new("Für den Schüler ist kein aktueller Kontakt ausgewählt.", true));
+        if (LetterDate is null)
+            Issues.Add(new("Bitte ein Briefdatum auswählen.", true));
+
+        if (SelectedTemplate is not null)
+        {
+            var validation = _templates.Validate(SelectedTemplate.Model);
+            foreach (var issue in validation.Issues)
+                Issues.Add(new(issue.Message, issue.Severity is TemplateIssueSeverity.StrongWarning or TemplateIssueSeverity.Error));
+
+            var tags = validation.Tags.ToHashSet(StringComparer.Ordinal);
+            var values = BuildValues();
+            foreach (var tag in tags.Where(t => values.TryGetValue(t, out var value) && string.IsNullOrWhiteSpace(value)))
+            {
+                var message = tag switch
+                {
+                    "Letter.Salutation" => "Beim ausgewählten Kontakt fehlt die Briefanrede.",
+                    "Contact.Address" or "Contact.Street" or "Contact.PostalCode" or "Contact.City" =>
+                        $"Beim ausgewählten Kontakt fehlt der Wert für „{tag}“.",
+                    "Group.Name" or "SchoolYear" => "Die Vorlage verwendet Gruppendaten; bitte eine Lerngruppe auswählen.",
+                    _ => $"Für das Vorlagenfeld „{tag}“ ist kein Wert vorhanden.",
+                };
+                Issues.Add(new(message, true));
+            }
+        }
+
+        CanGenerate = SelectedTemplate is not null && SelectedContact is not null && LetterDate is not null
+                      && Issues.Count == 0;
+        OnPropertyChanged(nameof(HasIssues));
+    }
+
+    private IReadOnlyDictionary<string, string?> BuildValues()
+    {
+        var contact = SelectedContact?.Model;
+        var group = SelectedGroup?.Model;
+        var cityLine = string.Join(" ", new[] { contact?.PostalCode, contact?.City }
+            .Where(v => !string.IsNullOrWhiteSpace(v)));
+        var address = string.Join(Environment.NewLine, new[] { contact?.Street, cityLine }
+            .Where(v => !string.IsNullOrWhiteSpace(v)));
+        var date = LetterDate is null ? null : DateOnly.FromDateTime(LetterDate.Value.LocalDateTime)
+            .ToString("dd.MM.yyyy", CultureInfo.GetCultureInfo("de-DE"));
+
+        return new Dictionary<string, string?>
+        {
+            ["Student.FirstName"] = _student.FirstName,
+            ["Student.LastName"] = _student.LastName,
+            ["Contact.Name"] = contact?.Name,
+            ["Contact.Address"] = address,
+            ["Contact.Street"] = contact?.Street,
+            ["Contact.PostalCode"] = contact?.PostalCode,
+            ["Contact.City"] = contact?.City,
+            ["Letter.Salutation"] = contact?.LetterSalutation,
+            ["Group.Name"] = group?.Name,
+            ["SchoolYear"] = group?.SchoolYear,
+            ["CurrentDate"] = date,
+        };
+    }
+
+    private static string SanitizeFileName(string value)
+    {
+        foreach (var character in Path.GetInvalidFileNameChars()) value = value.Replace(character, '_');
+        return value;
+    }
+}
+
+public sealed class LetterTemplateChoice
+{
+    public LetterTemplateInfo Model { get; }
+    public string Name => Model.Name;
+    public LetterTemplateChoice(LetterTemplateInfo model) => Model = model;
+}
+
+public sealed class LetterContactChoice
+{
+    public Contact Model { get; }
+    public string Display => string.IsNullOrWhiteSpace(Model.Relation)
+        ? Model.Name
+        : $"{Model.Name} · {Model.Relation}";
+    public LetterContactChoice(Contact model) => Model = model;
+}
+
+public sealed class LetterGroupChoice
+{
+    public LearningGroup Model { get; }
+    public string Display => $"{Model.Name} · {Model.SchoolYear}";
+    public LetterGroupChoice(LearningGroup model) => Model = model;
+}
+
+public sealed class LetterGenerationIssue(string message, bool isStrong)
+{
+    public string Icon { get; } = isStrong ? "⚠" : "ⓘ";
+    public string Message { get; } = message;
+    public string Color { get; } = isStrong ? "#D97706" : "#6B7280";
+}
@@ -9,9 +9,56 @@ using System.Globalization;

 namespace LehrerApp.Desktop.ViewModels.Students;

+public static class GenderAvatarDisplay
+{
+    public static List<string> Options { get; } = ["", "M – männlich", "W – weiblich", "D – divers"];
+
+    public static string Label(Gender? gender) => gender switch
+    {
+        Gender.M => "M",
+        Gender.W => "W",
+        Gender.D => "D",
+        _ => "?",
+    };
+
+    public static string Color(Gender? gender) => gender switch
+    {
+        Gender.M => "#3B82F6",
+        Gender.W => "#A855F7",
+        Gender.D => "#0D9488",
+        _ => "#6B7280",
+    };
+
+    public static string Tooltip(Gender? gender) => gender switch
+    {
+        Gender.M => "Geschlecht: männlich",
+        Gender.W => "Geschlecht: weiblich",
+        Gender.D => "Geschlecht: divers",
+        _ => "Geschlecht nicht angegeben",
+    };
+
+    public static string ToOption(Gender? gender) => gender switch
+    {
+        Gender.M => "M – männlich",
+        Gender.W => "W – weiblich",
+        Gender.D => "D – divers",
+        _ => "",
+    };
+
+    public static Gender? FromOption(string? option) => option switch
+    {
+        "M – männlich" => Gender.M,
+        "W – weiblich" => Gender.W,
+        "D – divers" => Gender.D,
+        _ => null,
+    };
+}
+
 public partial class StudentListViewModel : ObservableObject
 {
    private readonly IStudentRepository _students;
+    private readonly IGroupRepository _groups;
+    private readonly IGroupMembershipRepository _memberships;
    public Action<Guid>? OnNavigateToDetail { get; set; }

    [ObservableProperty] private string _searchText = "";
@@ -21,9 +68,12 @@ public partial class StudentListViewModel : ObservableObject
    public ObservableCollection<StudentListItem> Students { get; } = [];
    public string CountSummary => $"{Students.Count} Schüler gesamt";

-    public StudentListViewModel(IStudentRepository students)
+    public StudentListViewModel(IStudentRepository students, IGroupRepository groups,
+        IGroupMembershipRepository memberships)
    {
        _students = students;
+        _groups = groups;
+        _memberships = memberships;
        LoadStudents();
    }

@@ -38,9 +88,21 @@ public partial class StudentListViewModel : ObservableObject
    {
        Students.Clear();
        var all = _students.GetAll(ShowInactive);
-        var f = string.IsNullOrWhiteSpace(SearchText) ? all
-            : all.Where(s => s.LastName.Contains(SearchText, StringComparison.OrdinalIgnoreCase)
-                          || s.FirstName.Contains(SearchText, StringComparison.OrdinalIgnoreCase));
+        var query = SearchText.Trim();
+        IEnumerable<Student> f = all;
+        if (query.Length > 0)
+        {
+            var matchingStudentIds = _groups.GetAll(includeInactive: true)
+                .Where(g => g.Name.Contains(query, StringComparison.OrdinalIgnoreCase))
+                .SelectMany(g => _memberships.GetByGroup(g.Id))
+                .Select(m => m.StudentId)
+                .ToHashSet();
+
+            f = all.Where(s => s.LastName.Contains(query, StringComparison.OrdinalIgnoreCase)
+                            || s.FirstName.Contains(query, StringComparison.OrdinalIgnoreCase)
+                            || s.FullName.Contains(query, StringComparison.OrdinalIgnoreCase)
+                            || matchingStudentIds.Contains(s.Id));
+        }
        foreach (var s in f) Students.Add(new StudentListItem(s));
        OnPropertyChanged(nameof(CountSummary));
    }
@@ -63,10 +125,92 @@ public class StudentListItem
    public Guid Id { get; }
    public string FullName { get; }
    public string DateOfBirth { get; }
+    public string AvatarLabel { get; }
+    public string AvatarColor { get; }
+    public string AvatarTooltip { get; }
    public StudentListItem(Student s)
    {
        Id = s.Id; FullName = s.FullName;
        DateOfBirth = s.DateOfBirth?.ToString("dd.MM.yyyy") ?? "";
+        AvatarLabel = GenderAvatarDisplay.Label(s.Gender);
+        AvatarColor = GenderAvatarDisplay.Color(s.Gender);
+        AvatarTooltip = GenderAvatarDisplay.Tooltip(s.Gender);
+    }
+}
+
+public enum StudentManagementResult { Cancelled, Deactivated, Reactivated, Deleted }
+
+public class StudentReferenceItem(string label, int count)
+{
+    public string Label { get; } = label;
+    public int Count { get; } = count;
+    public string CountDisplay => Count.ToString(CultureInfo.InvariantCulture);
+}
+
+public partial class ManageStudentDialogViewModel : ObservableObject
+{
+    private readonly IStudentRepository _students;
+    private readonly Student _student;
+
+    [ObservableProperty] private string _errorMessage = "";
+
+    public string StudentName => _student.FullName;
+    public bool IsActive => _student.IsActive;
+    public bool IsInactive => !IsActive;
+    public StudentReferenceSummary References { get; }
+    public bool HasReferences => References.HasReferences;
+    public bool CanDelete => !HasReferences;
+    public ObservableCollection<StudentReferenceItem> ReferenceItems { get; } = [];
+    public StudentManagementResult Result { get; private set; }
+
+    public ManageStudentDialogViewModel(IStudentRepository students, Student student)
+    {
+        _students = students;
+        _student = student;
+        References = students.GetReferenceSummary(student.Id);
+
+        AddReference("Gruppenzuordnungen", References.Memberships);
+        AddReference("Klausurergebnisse", References.ExamResults);
+        AddReference("Einzelnoten", References.Grades);
+        AddReference("Zeugnisnoten", References.ReportGrades);
+        AddReference("Mitarbeitseinträge", References.ParticipationEntries);
+        AddReference("Dokumentationseinträge", References.DocumentationEntries);
+    }
+
+    [RelayCommand]
+    private void Deactivate()
+    {
+        _student.IsActive = false;
+        _students.Save(_student);
+        Result = StudentManagementResult.Deactivated;
+    }
+
+    [RelayCommand]
+    private void Reactivate()
+    {
+        _student.IsActive = true;
+        _students.Save(_student);
+        Result = StudentManagementResult.Reactivated;
+    }
+
+    [RelayCommand(CanExecute = nameof(CanDelete))]
+    private void DeletePermanently()
+    {
+        ErrorMessage = "";
+        try
+        {
+            _students.Delete(_student.Id);
+            Result = StudentManagementResult.Deleted;
+        }
+        catch (InvalidOperationException ex)
+        {
+            ErrorMessage = ex.Message;
+        }
+    }
+
+    private void AddReference(string label, int count)
+    {
+        if (count > 0) ReferenceItems.Add(new StudentReferenceItem(label, count));
    }
 }

@@ -91,9 +235,17 @@ public partial class StudentDetailViewModel : ObservableObject
    [ObservableProperty] private bool _isEditing;
    [ObservableProperty] private string _editFirstName = "";
    [ObservableProperty] private string _editLastName = "";
+    [ObservableProperty] private string _editGender = "";
    [ObservableProperty] private ContactItem? _selectedContact;
    [ObservableProperty] private AttendanceBalance? _attendance;
    [ObservableProperty] private string _exportStatus = "";
+    [ObservableProperty] private bool _isStudentActive = true;
+
+    public string StudentStatus => IsStudentActive ? "Aktiv" : "Inaktiv";
+    public List<string> GenderOptions => GenderAvatarDisplay.Options;
+    public string StudentAvatarLabel => GenderAvatarDisplay.Label(Student?.Gender);
+    public string StudentAvatarColor => GenderAvatarDisplay.Color(Student?.Gender);
+    public string StudentAvatarTooltip => GenderAvatarDisplay.Tooltip(Student?.Gender);

    public ObservableCollection<GroupMembershipEntry> GroupMemberships { get; } = [];
    public ObservableCollection<DocumentationItem>    Documentation { get; } = [];
@@ -106,6 +258,11 @@ public partial class StudentDetailViewModel : ObservableObject
    public Func<DocumentationItem, Task<bool>>? OnConfirmDeleteDocumentation { get; set; }
    public Func<string, Task>? OnSaveExportFile { get; set; }
    public Func<Documentation, string, Task<Documentation?>>? OnConductParentCall { get; set; }
+    public Func<Student, Task<StudentManagementResult>>? OnManageStudent { get; set; }
+    public Func<Task>? OnCreateLetter { get; set; }
+    public Action? OnReturnToStudentList { get; set; }
+
+    partial void OnIsStudentActiveChanged(bool value) => OnPropertyChanged(nameof(StudentStatus));

    public StudentDetailViewModel(IStudentRepository students,
        IGroupMembershipRepository memberships, IGroupRepository groups, ISubjectRepository subjects,
@@ -126,8 +283,13 @@ public partial class StudentDetailViewModel : ObservableObject
        Student = _students.GetById(id);
        if (Student is null) return;
        StudentTitle  = Student.FullName;
+        IsStudentActive = Student.IsActive;
        EditFirstName = Student.FirstName;
        EditLastName  = Student.LastName;
+        EditGender = GenderAvatarDisplay.ToOption(Student.Gender);
+        OnPropertyChanged(nameof(StudentAvatarLabel));
+        OnPropertyChanged(nameof(StudentAvatarColor));
+        OnPropertyChanged(nameof(StudentAvatarTooltip));

        GroupMemberships.Clear();
        GradeHistory.Clear();
@@ -269,18 +431,44 @@ public partial class StudentDetailViewModel : ObservableObject
    }

    [RelayCommand] private void StartEdit() => IsEditing = true;
+
+    [RelayCommand]
+    private async Task CreateLetter()
+    {
+        if (Student is not null && OnCreateLetter is not null) await OnCreateLetter();
+    }
+
+    [RelayCommand]
+    private async Task ManageStudent()
+    {
+        if (Student is null || OnManageStudent is null) return;
+        var result = await OnManageStudent(Student);
+        if (result == StudentManagementResult.Deleted)
+        {
+            OnReturnToStudentList?.Invoke();
+            return;
+        }
+        if (result is StudentManagementResult.Deactivated or StudentManagementResult.Reactivated)
+            LoadStudent(Student.Id);
+    }
+
    [RelayCommand] private void CancelEdit()
    {
        if (Student is null) return;
        EditFirstName = Student.FirstName; EditLastName = Student.LastName;
+        EditGender = GenderAvatarDisplay.ToOption(Student.Gender);
        IsEditing = false;
    }
    [RelayCommand] private void SaveEdit()
    {
        if (Student is null) return;
        Student.FirstName = EditFirstName; Student.LastName = EditLastName;
+        Student.Gender = GenderAvatarDisplay.FromOption(EditGender);
        _students.Save(Student);
        StudentTitle = Student.FullName;
+        OnPropertyChanged(nameof(StudentAvatarLabel));
+        OnPropertyChanged(nameof(StudentAvatarColor));
+        OnPropertyChanged(nameof(StudentAvatarTooltip));
        IsEditing = false;
    }

@@ -382,6 +570,7 @@ public class ContactItem
    public Guid    Id        => Model.Id;
    public string  Name      { get; }
    public string  Relation  { get; }
+    public string  LetterSalutation { get; }
    public string? Phone     { get; }
    public string? Email     { get; }
    public string  Address   { get; }
@@ -404,6 +593,7 @@ public class ContactItem
        Model    = c;
        Name     = c.Name;
        Relation = c.Relation;
+        LetterSalutation = c.LetterSalutation ?? "";
        Phone    = c.Phone;
        Email    = c.Email;
        Address  = FormatAddress(c);
@@ -449,7 +639,7 @@ public partial class AddStudentDialogViewModel : ObservableObject
    [ObservableProperty] private string _firstNameError = "";
    [ObservableProperty] private string _dateOfBirthError = "";

-    public List<string> GenderOptions    { get; } = ["", "M – männlich", "W – weiblich", "D – divers"];
+    public List<string> GenderOptions => GenderAvatarDisplay.Options;
    public List<string> RelationPresets  { get; } = ["Schüler/in", "Mutter", "Vater", "Elternteil", "Erziehungsberechtigte/r", "Sonstige"];

    public ObservableCollection<ContactEntryViewModel> Contacts { get; } = [];
@@ -490,13 +680,7 @@ public partial class AddStudentDialogViewModel : ObservableObject
            FirstName   = FirstName.Trim(),
            LastName    = LastName.Trim(),
            DateOfBirth = dob,
-            Gender      = SelectedGender switch
-            {
-                "M – männlich" => Gender.M,
-                "W – weiblich" => Gender.W,
-                "D – divers"   => Gender.D,
-                _              => (Gender?)null,
-            },
+            Gender      = GenderAvatarDisplay.FromOption(SelectedGender),
            Notes    = string.IsNullOrWhiteSpace(Notes) ? null : Notes.Trim(),
            Contacts = Contacts.Select(c => c.ToModel()).Where(c => !string.IsNullOrWhiteSpace(c.Name)).ToList(),
        };
@@ -510,6 +694,7 @@ public partial class ContactEntryViewModel : ObservableObject

    [ObservableProperty] private string _name     = "";
    [ObservableProperty] private string _relation = "";
+    [ObservableProperty] private string _letterSalutation = "";
    [ObservableProperty] private string _phone    = "";
    [ObservableProperty] private string _email    = "";
    [ObservableProperty] private string _street = "";
@@ -524,6 +709,7 @@ public partial class ContactEntryViewModel : ObservableObject
    {
        Name     = Name.Trim(),
        Relation = Relation.Trim(),
+        LetterSalutation = string.IsNullOrWhiteSpace(LetterSalutation) ? null : LetterSalutation.Trim(),
        Phone    = string.IsNullOrWhiteSpace(Phone) ? null : Phone.Trim(),
        Email    = string.IsNullOrWhiteSpace(Email) ? null : Email.Trim(),
        Street   = string.IsNullOrWhiteSpace(Street) ? null : Street.Trim(),
@@ -538,6 +724,7 @@ public partial class ContactEditDialogViewModel : ObservableObject

    [ObservableProperty] private string _name = "";
    [ObservableProperty] private string _relation = "Elternteil";
+    [ObservableProperty] private string _letterSalutation = "";
    [ObservableProperty] private string _phone = "";
    [ObservableProperty] private string _email = "";
    [ObservableProperty] private string _street = "";
@@ -564,6 +751,7 @@ public partial class ContactEditDialogViewModel : ObservableObject
        if (source is null) return;
        Name = source.Name;
        Relation = source.Relation;
+        LetterSalutation = source.LetterSalutation ?? "";
        Phone = source.Phone ?? "";
        Email = source.Email ?? "";
        Street = source.Street ?? "";
@@ -614,6 +802,7 @@ public partial class ContactEditDialogViewModel : ObservableObject
            Id = _source?.Id ?? Guid.NewGuid(),
            Name = Name.Trim(),
            Relation = Relation.Trim(),
+            LetterSalutation = NullIfEmpty(LetterSalutation),
            Phone = NullIfEmpty(Phone),
            Email = NullIfEmpty(Email),
            Street = NullIfEmpty(Street),
@@ -17,9 +17,10 @@
      <Button Content="Sortierung: Gesamt" Command="{Binding SortByTotalCommand}"/>

      <Button Content="Noten verwalten" Command="{Binding ManageStudentGradesCommand}" Margin="12,0,0,0"
-              IsVisible="{Binding SelectedRow, Converter={x:Static ObjectConverters.IsNotNull}}"/>
-      <Button Content="＋ Sammelnote" Command="{Binding CollectiveGradeCommand}"/>
-      <Button Content="Zeugnisnoten" Command="{Binding ReportGradesCommand}"/>
+              IsVisible="{Binding SelectedRow, Converter={x:Static ObjectConverters.IsNotNull}}"
+              IsEnabled="{Binding !IsReadOnly}"/>
+      <Button Content="＋ Sammelnote" Command="{Binding CollectiveGradeCommand}" IsEnabled="{Binding !IsReadOnly}"/>
+      <Button Content="Zeugnisnoten" Command="{Binding ReportGradesCommand}" IsEnabled="{Binding !IsReadOnly}"/>
    </StackPanel>

    <DataGrid Grid.Row="1"
@@ -7,7 +7,7 @@
             x:Class="LehrerApp.Desktop.Views.Groups.GroupDetailView"
             x:DataType="vm:GroupDetailViewModel">

-  <Grid RowDefinitions="Auto,*">
+  <Grid RowDefinitions="Auto,Auto,*">

    <!-- Header -->
    <Border Grid.Row="0" Padding="20,16"
@@ -22,18 +22,32 @@
          </TextBlock>
          <CheckBox Content="Ausgetretene anzeigen" IsChecked="{Binding ShowFormerStudents}"
                    VerticalAlignment="Center"/>
-          <Button Content="＋ Schüler"   Command="{Binding AddStudentCommand}"/>
+          <Button Content="＋ Schüler" Command="{Binding AddStudentCommand}" IsEnabled="{Binding IsEditable}"/>
          <Button Content="{Binding SelectedStudent.WithdrawActionLabel}"
                  Command="{Binding WithdrawStudentCommand}"
                  IsVisible="{Binding SelectedStudent, Converter={x:Static ObjectConverters.IsNotNull}}"/>
          <Button Content="Austragung zurücknehmen" Command="{Binding ReinstateStudentCommand}"
                  IsVisible="{Binding SelectedStudent.HasExitDate}"/>
-          <Button Content="＋ Klausur"   Command="{Binding AddExamCommand}"/>
+          <Button Content="＋ Klausur" Command="{Binding AddExamCommand}" IsEnabled="{Binding IsEditable}"/>
        </StackPanel>
      </Grid>
    </Border>

-    <TabbedPage Grid.Row="1" TabPlacement="Top" SelectedIndex="{Binding ActiveTabIndex}">
+    <Border Grid.Row="1" Background="#FFF3CD" BorderBrush="#D97706" BorderThickness="0,0,0,1"
+            Padding="20,10" IsVisible="{Binding IsReadOnly}">
+      <Grid ColumnDefinitions="*,Auto">
+        <StackPanel Grid.Column="0" Spacing="2">
+          <TextBlock Text="Archivierte Lerngruppe · schreibgeschützt" FontWeight="SemiBold"
+                     Foreground="#92400E"/>
+          <TextBlock Text="Alle historischen Daten bleiben sichtbar. Für Korrekturen muss die Gruppe ausdrücklich wieder aktiviert werden."
+                     FontSize="12" Foreground="#92400E" TextWrapping="Wrap"/>
+        </StackPanel>
+        <Button Grid.Column="1" Content="Gruppe wieder aktivieren"
+                Command="{Binding ReactivateGroupCommand}" Margin="16,0,0,0"/>
+      </Grid>
+    </Border>
+
+    <TabbedPage Grid.Row="2" TabPlacement="Top" SelectedIndex="{Binding ActiveTabIndex}">

      <!-- Tab: Übersicht -->
      <ContentPage Header="Übersicht">
@@ -57,6 +71,18 @@
                  CanUserResizeColumns="True"
                  Margin="0">
          <DataGrid.Columns>
+            <DataGridTemplateColumn Header="" Width="48">
+              <DataGridTemplateColumn.CellTemplate>
+                <DataTemplate x:DataType="vm:StudentSummary">
+                  <Border Width="30" Height="30" CornerRadius="15" Background="{Binding AvatarColor}"
+                          HorizontalAlignment="Center" VerticalAlignment="Center"
+                          ToolTip.Tip="{Binding AvatarTooltip}">
+                    <TextBlock Text="{Binding AvatarLabel}" Foreground="White" FontWeight="Bold"
+                               HorizontalAlignment="Center" VerticalAlignment="Center"/>
+                  </Border>
+                </DataTemplate>
+              </DataGridTemplateColumn.CellTemplate>
+            </DataGridTemplateColumn>
            <DataGridTextColumn Header="Name"     Binding="{Binding FullName}"         Width="*"/>
            <DataGridTextColumn Header="Zeitraum" Binding="{Binding PeriodLabel}"      Width="190"/>
            <DataGridTextColumn Header="Status"   Binding="{Binding MembershipStatus}" Width="170"/>
@@ -66,6 +92,7 @@
                <DataTemplate x:DataType="vm:StudentSummary">
                  <ComboBox ItemsSource="{x:Static vm:StudentSummary.NiveauOptions}"
                            SelectedItem="{Binding NiveauName}"
+                            IsEnabled="{Binding CanEdit}"
                            HorizontalAlignment="Stretch" Margin="2"/>
                </DataTemplate>
              </DataGridTemplateColumn.CellTemplate>
@@ -83,7 +110,8 @@
      <ContentPage Header="Klausuren">
        <Grid RowDefinitions="Auto,*">
          <StackPanel Grid.Row="0" Orientation="Horizontal" Spacing="8" Margin="0,0,0,8"
-                      IsVisible="{Binding SelectedExam, Converter={x:Static ObjectConverters.IsNotNull}}">
+                      IsVisible="{Binding SelectedExam, Converter={x:Static ObjectConverters.IsNotNull}}"
+                      IsEnabled="{Binding IsEditable}">
            <Button Content="Punkte eingeben" Command="{Binding GradeExamCommand}"/>
            <Button Content="Auswertung"    Command="{Binding EvaluateExamCommand}"/>
            <Button Content="Bearbeiten"    Command="{Binding EditExamCommand}"/>
@@ -3,6 +3,7 @@ using LehrerApp.Core.Interfaces;
 using LehrerApp.Core.Models;
 using LehrerApp.Core.Services;
 using LehrerApp.Desktop.ViewModels.Groups;
+using LehrerApp.Desktop.Views.Shared;
 using Microsoft.Extensions.DependencyInjection;

 namespace LehrerApp.Desktop.Views.Groups;
@@ -24,9 +25,25 @@ public partial class GroupDetailView : UserControl
            vm.OnConfirmDeleteExam = ShowDeleteExamDialog;
            vm.OnGradeExam       = ShowGradeExamDialog;
            vm.OnEvaluateExam    = ShowEvaluateExamDialog;
+            vm.OnConfirmReactivate = ShowReactivateConfirmDialog;
        }
    }

+    private async Task<bool> ShowReactivateConfirmDialog()
+    {
+        var dialog = new ConfirmDialog
+        {
+            DataContext = new ConfirmDialogInfo
+            {
+                Title = "Archivierte Gruppe wieder aktivieren?",
+                Message = "Nach der Wiederaktivierung können historische Daten dieser Gruppe wieder verändert werden.",
+                ConfirmText = "Wieder aktivieren",
+            },
+        };
+        var owner = TopLevel.GetTopLevel(this) as Window;
+        return owner is not null && await dialog.ShowDialog<bool>(owner);
+    }
+
    private async Task<bool> ShowAddStudentDialog()
    {
        if (DataContext is not GroupDetailViewModel vm || vm.Group is null) return false;
@@ -91,6 +91,8 @@
                <MenuFlyout>
                  <MenuItem Header="Details bearbeiten"
                            Command="{Binding EditGroupCommand}"/>
+                  <MenuItem Header="Ins nächste Schuljahr übernehmen …"
+                            Command="{Binding RollOverGroupCommand}"/>
                  <MenuItem Header="{Binding SelectedGroup.ArchiveActionLabel}"
                            Command="{Binding ToggleArchiveCommand}"/>
                  <Separator/>
@@ -15,6 +15,7 @@ public partial class GroupListView : UserControl
        {
            vm.OnAddGroup = ShowAddGroupDialog;
            vm.OnEditGroup = ShowEditGroupDialog;
+            vm.OnRollOverGroup = ShowGroupRolloverDialog;
            vm.OnConfirmDelete = ShowDeleteGroupDialog;
        }
    }
@@ -42,6 +43,23 @@ public partial class GroupListView : UserControl
            await dialog.ShowDialog<bool>(owner);
    }

+    private async Task<Guid?> ShowGroupRolloverDialog(Guid groupId)
+    {
+        var group = App.Services.GetRequiredService<LehrerApp.Core.Interfaces.IGroupRepository>()
+            .GetById(groupId);
+        var owner = TopLevel.GetTopLevel(this) as Window;
+        if (group is null || owner is null) return null;
+
+        var dialogVm = new GroupRolloverDialogViewModel(group,
+            App.Services.GetRequiredService<LehrerApp.Core.Interfaces.IStudentRepository>(),
+            App.Services.GetRequiredService<LehrerApp.Core.Interfaces.IGroupMembershipRepository>(),
+            App.Services.GetRequiredService<LehrerApp.Core.Interfaces.IGradingSchemeRepository>(),
+            App.Services.GetRequiredService<LehrerApp.Core.Services.SchoolYearService>(),
+            App.Services.GetRequiredService<LehrerApp.Core.Services.GroupRolloverService>());
+        var dialog = new GroupRolloverDialog { DataContext = dialogVm };
+        return await dialog.ShowDialog<Guid?>(owner);
+    }
+
    private async Task<bool> ShowDeleteGroupDialog(GroupListItem group)
    {
        var dialog = new DeleteGroupDialog { DataContext = group.DisplayName };
@@ -0,0 +1,75 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Groups"
+        x:Class="LehrerApp.Desktop.Views.Groups.GroupRolloverDialog"
+        x:DataType="vm:GroupRolloverDialogViewModel"
+        Title="Ins nächste Schuljahr übernehmen"
+        Width="650" Height="720" MinWidth="560" MinHeight="600"
+        CanResize="True" WindowStartupLocation="CenterOwner">
+  <Grid RowDefinitions="Auto,*,Auto" Margin="24,20">
+    <StackPanel Grid.Row="0" Spacing="12">
+      <TextBlock Text="Ins nächste Schuljahr übernehmen" Classes="dialogtitle"/>
+      <TextBlock Text="{Binding SourceSummary}" FontSize="12" Opacity="0.65"/>
+      <TextBlock Text="Es werden nur Gruppeneinstellungen und ausgewählte Mitgliedschaften kopiert. Noten, Klausuren, Mitarbeit, Planung und Stundenplan bleiben im alten Schuljahr."
+                 FontSize="12" Opacity="0.65" TextWrapping="Wrap"/>
+
+      <Grid ColumnDefinitions="*,12,130,12,100">
+        <StackPanel Grid.Column="0" Spacing="4">
+          <TextBlock Text="Neuer Gruppenname *" FontSize="12" Opacity="0.7"/>
+          <TextBox Text="{Binding Name}"/>
+          <TextBlock Text="{Binding NameError}" Foreground="Red" FontSize="11"
+                     IsVisible="{Binding NameError, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+        </StackPanel>
+        <StackPanel Grid.Column="2" Spacing="4">
+          <TextBlock Text="Zielschuljahr *" FontSize="12" Opacity="0.7"/>
+          <TextBox Text="{Binding TargetSchoolYear}" PlaceholderText="2027/28"/>
+          <TextBlock Text="{Binding SchoolYearError}" Foreground="Red" FontSize="11"
+                     IsVisible="{Binding SchoolYearError, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+        </StackPanel>
+        <StackPanel Grid.Column="4" Spacing="4">
+          <TextBlock Text="Klassenstufe" FontSize="12" Opacity="0.7"/>
+          <NumericUpDown Value="{Binding GradeLevel}" Minimum="1" Maximum="13" FormatString="0"/>
+        </StackPanel>
+      </Grid>
+
+      <Grid ColumnDefinitions="*,Auto">
+        <TextBlock Grid.Column="0" Text="Schülerauswahl" FontSize="14" FontWeight="SemiBold"/>
+        <TextBlock Grid.Column="1" Text="{Binding SelectedCountText}" FontSize="12" Opacity="0.6"/>
+      </Grid>
+    </StackPanel>
+
+    <Grid Grid.Row="1" RowDefinitions="*,Auto" Margin="0,10,0,0">
+      <ListBox Grid.Row="0" ItemsSource="{Binding Students}">
+        <ListBox.ItemTemplate>
+          <DataTemplate x:DataType="vm:GroupRolloverStudentItem">
+            <Grid ColumnDefinitions="Auto,*,70" Margin="4,5">
+              <CheckBox Grid.Column="0" IsChecked="{Binding IsSelected}" IsEnabled="{Binding CanSelect}"
+                        VerticalAlignment="Center" Margin="0,0,10,0"/>
+              <StackPanel Grid.Column="1">
+                <TextBlock Text="{Binding FullName}" FontSize="13" FontWeight="SemiBold"/>
+                <TextBlock Text="{Binding MembershipStatus}" FontSize="11" Opacity="0.55"/>
+              </StackPanel>
+              <TextBlock Grid.Column="2" Text="{Binding NiveauText}" FontSize="12" Opacity="0.65"
+                         HorizontalAlignment="Center" VerticalAlignment="Center"/>
+            </Grid>
+          </DataTemplate>
+        </ListBox.ItemTemplate>
+      </ListBox>
+      <TextBlock Grid.Row="1" Text="{Binding SelectionError}" Foreground="Red" FontSize="11" Margin="0,5,0,0"
+                 IsVisible="{Binding SelectionError, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+    </Grid>
+
+    <StackPanel Grid.Row="2" Spacing="10" Margin="0,14,0,0">
+      <CheckBox Content="Gruppenspezifisches Notenschema übernehmen"
+                IsChecked="{Binding CopyGradingScheme}" IsVisible="{Binding HasGradingScheme}"/>
+      <CheckBox Content="Alte Gruppe nach erfolgreicher Übernahme archivieren"
+                IsChecked="{Binding ArchiveSource}"/>
+      <TextBlock Text="{Binding GeneralError}" Foreground="Red" FontSize="12" TextWrapping="Wrap"
+                 IsVisible="{Binding GeneralError, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+      <Grid ColumnDefinitions="*,10,*">
+        <Button Grid.Column="0" Content="Abbrechen" HorizontalAlignment="Stretch" Click="OnCancel"/>
+        <Button Grid.Column="2" Content="Gruppe übernehmen" HorizontalAlignment="Stretch" Click="OnSave"/>
+      </Grid>
+    </StackPanel>
+  </Grid>
+</Window>
@@ -0,0 +1,19 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using LehrerApp.Desktop.ViewModels.Groups;
+
+namespace LehrerApp.Desktop.Views.Groups;
+
+public partial class GroupRolloverDialog : Window
+{
+    public GroupRolloverDialog() => InitializeComponent();
+
+    private void OnSave(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not GroupRolloverDialogViewModel vm) return;
+        vm.SaveCommand.Execute(null);
+        if (vm.Result is not null) Close(vm.Result.Id);
+    }
+
+    private void OnCancel(object? sender, RoutedEventArgs e) => Close(null);
+}
@@ -13,19 +13,19 @@
    <Grid RowDefinitions="Auto,Auto,Auto,Auto,*">

      <Button Grid.Row="0" Content="＋ Sitzung" Command="{Binding AddSessionCommand}"
-              HorizontalAlignment="Stretch" Margin="10,10,10,6"/>
+              HorizontalAlignment="Stretch" Margin="10,10,10,6" IsEnabled="{Binding !IsReadOnly}"/>

      <StackPanel Grid.Row="1" Orientation="Horizontal" Spacing="6" Margin="10,0,10,6">
        <Button Content="Schnell Mitarbeit" Command="{Binding QuickInputCommand}"
-                HorizontalAlignment="Stretch"/>
-        <Button Content="Anw./HA" Command="{Binding StatusQuickInputCommand}"/>
+                HorizontalAlignment="Stretch" IsEnabled="{Binding !IsReadOnly}"/>
+        <Button Content="Anw./HA" Command="{Binding StatusQuickInputCommand}" IsEnabled="{Binding !IsReadOnly}"/>
      </StackPanel>

      <Button Grid.Row="2" Content="Ø Mitarbeitsnote" Command="{Binding ComputeGradeCommand}"
-              HorizontalAlignment="Stretch" Margin="10,0,10,6"/>
+              HorizontalAlignment="Stretch" Margin="10,0,10,6" IsEnabled="{Binding !IsReadOnly}"/>

      <Button Grid.Row="3" Content="Mitarbeits-Assistent" Command="{Binding OpenWizardCommand}"
-              HorizontalAlignment="Stretch" Margin="10,0,10,6"/>
+              HorizontalAlignment="Stretch" Margin="10,0,10,6" IsEnabled="{Binding !IsReadOnly}"/>

      <ListBox Grid.Row="4"
               ItemsSource="{Binding Sessions}"
@@ -68,7 +68,7 @@
              BorderThickness="0,0,0,1"
              Padding="12,8">
        <ScrollViewer HorizontalScrollBarVisibility="Disabled" MaxHeight="200">
-          <ItemsControl ItemsSource="{Binding CompetencyTagGroups}">
+          <ItemsControl ItemsSource="{Binding CompetencyTagGroups}" IsEnabled="{Binding !IsReadOnly}">
            <ItemsControl.ItemTemplate>
              <DataTemplate DataType="vm:CompetencyTagGroup">
                <StackPanel Spacing="4" Margin="0,0,0,10">
@@ -58,7 +58,7 @@ public partial class ParticipationTabView : UserControl
            {
                Header       = $"{aspect.Label}  [{AspectShortcut(i)}]",
                Width        = new DataGridLength(1, DataGridLengthUnitType.Star),
-                CellTemplate = BuildCellTemplate(idx, forCompetency: false),
+                CellTemplate = BuildCellTemplate(idx, forCompetency: false, _vm.IsReadOnly),
            });
        }

@@ -66,13 +66,13 @@ public partial class ParticipationTabView : UserControl
        {
            Header       = "HA",
            Width        = new DataGridLength(50, DataGridLengthUnitType.Pixel),
-            CellTemplate = BuildHomeworkCellTemplate(),
+            CellTemplate = BuildHomeworkCellTemplate(_vm.IsReadOnly),
        });
        grid.Columns.Add(new DataGridTemplateColumn
        {
            Header       = "Anwesenheit",
            Width        = new DataGridLength(80, DataGridLengthUnitType.Pixel),
-            CellTemplate = BuildAttendanceCellTemplate(),
+            CellTemplate = BuildAttendanceCellTemplate(_vm.IsReadOnly),
        });

        // Kompetenz-Spalten (opt-in)
@@ -85,13 +85,13 @@ public partial class ParticipationTabView : UserControl
                {
                    Header       = code,
                    Width        = new DataGridLength(80, DataGridLengthUnitType.Pixel),
-                    CellTemplate = BuildCellTemplate(idx, forCompetency: true),
+                    CellTemplate = BuildCellTemplate(idx, forCompetency: true, _vm.IsReadOnly),
                });
            }
        }
    }

-    private static IDataTemplate BuildCellTemplate(int cellIndex, bool forCompetency)
+    private static IDataTemplate BuildCellTemplate(int cellIndex, bool forCompetency, bool isReadOnly)
    {
        return new FuncDataTemplate<ParticipationStudentRow>((row, _) =>
        {
@@ -119,6 +119,7 @@ public partial class ParticipationTabView : UserControl
                    Padding  = new Avalonia.Thickness(5, 1),
                    FontSize = 11,
                    Opacity  = cell.Value == val ? 1.0 : 0.3,
+                    IsEnabled = !isReadOnly,
                };
                var capturedVal = val;
                btn.Click += (_, _) => cell.SetValue(capturedVal);
@@ -134,7 +135,7 @@ public partial class ParticipationTabView : UserControl
        });
    }

-    private static IDataTemplate BuildHomeworkCellTemplate()
+    private static IDataTemplate BuildHomeworkCellTemplate(bool isReadOnly)
    {
        return new FuncDataTemplate<ParticipationStudentRow>((row, _) =>
        {
@@ -147,6 +148,7 @@ public partial class ParticipationTabView : UserControl
                Height = 26,
                Padding = new Avalonia.Thickness(3, 1),
                Command = row.ToggleHomeworkCommand,
+                IsEnabled = !isReadOnly,
            };
            void RefreshHomework()
            {
@@ -180,7 +182,7 @@ public partial class ParticipationTabView : UserControl
        });
    }

-    private static IDataTemplate BuildAttendanceCellTemplate()
+    private static IDataTemplate BuildAttendanceCellTemplate(bool isReadOnly)
    {
        return new FuncDataTemplate<ParticipationStudentRow>((row, _) =>
        {
@@ -193,6 +195,7 @@ public partial class ParticipationTabView : UserControl
                Height = 26,
                Padding = new Avalonia.Thickness(3, 1),
                Command = row.CycleAttendanceCommand,
+                IsEnabled = !isReadOnly,
            };
            void RefreshAttendance()
            {
@@ -11,10 +11,10 @@
      <TextBlock Grid.Column="0" Text="Unterrichtseinheiten" FontSize="14" FontWeight="SemiBold"
                 VerticalAlignment="Center"/>
      <StackPanel Grid.Column="1" Orientation="Horizontal" Spacing="8">
-        <Button Content="＋ Einheit"          Command="{Binding AddUnitCommand}"/>
-        <Button Content="Bearbeiten"          Command="{Binding EditUnitCommand}"/>
+        <Button Content="＋ Einheit"          Command="{Binding AddUnitCommand}" IsEnabled="{Binding !IsReadOnly}"/>
+        <Button Content="Bearbeiten"          Command="{Binding EditUnitCommand}" IsEnabled="{Binding !IsReadOnly}"/>
        <Button Content="Als Vorlage kopieren" Command="{Binding CopyUnitCommand}"/>
-        <Button Content="Löschen"             Command="{Binding DeleteUnitCommand}"/>
+        <Button Content="Löschen"             Command="{Binding DeleteUnitCommand}" IsEnabled="{Binding !IsReadOnly}"/>
      </StackPanel>
    </Grid>

@@ -62,15 +62,16 @@
        <TextBlock Text="{Binding SelectedUnitTitleSuffix}" FontSize="14" FontWeight="SemiBold"/>
      </StackPanel>
      <StackPanel Grid.Column="1" Orientation="Horizontal" Spacing="8">
-        <Button Content="＋ Stunde"              Command="{Binding AddLessonCommand}"/>
+        <Button Content="＋ Stunde"              Command="{Binding AddLessonCommand}" IsEnabled="{Binding !IsReadOnly}"/>
        <Button Content="Serie erzeugen"         Command="{Binding GenerateLessonSeriesCommand}"
+                IsEnabled="{Binding !IsReadOnly}"
                ToolTip.Tip="Stunden für alle Termine aus dem Stundenplan im gewählten Zeitraum anlegen."/>
        <Button Content="Anzeigen"               Command="{Binding ShowLessonCommand}"
                ToolTip.Tip="Verlaufsplan schreibgeschützt und größer anzeigen — zum Mitnehmen in den Unterricht."/>
-        <Button Content="Bearbeiten"             Command="{Binding EditLessonCommand}"/>
-        <Button Content="Verschieben"            Command="{Binding MoveLessonCommand}"/>
-        <Button Content="Status → Durchgeführt"  Command="{Binding AdvanceLessonStatusCommand}"/>
-        <Button Content="Löschen"                Command="{Binding DeleteLessonCommand}"/>
+        <Button Content="Bearbeiten"             Command="{Binding EditLessonCommand}" IsEnabled="{Binding !IsReadOnly}"/>
+        <Button Content="Verschieben"            Command="{Binding MoveLessonCommand}" IsEnabled="{Binding !IsReadOnly}"/>
+        <Button Content="Status → Durchgeführt"  Command="{Binding AdvanceLessonStatusCommand}" IsEnabled="{Binding !IsReadOnly}"/>
+        <Button Content="Löschen"                Command="{Binding DeleteLessonCommand}" IsEnabled="{Binding !IsReadOnly}"/>
      </StackPanel>
    </Grid>

@@ -1,6 +1,7 @@
 <UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Settings"
+             xmlns:services="clr-namespace:LehrerApp.Core.Services;assembly=LehrerApp.Core"
             xmlns:shared="clr-namespace:LehrerApp.Desktop.Views.Shared"
             x:Class="LehrerApp.Desktop.Views.Settings.SettingsView"
             x:DataType="vm:SettingsViewModel">
@@ -270,6 +271,86 @@
        </ScrollViewer>
      </ContentPage>

+      <!-- Tab: Word-Briefvorlagen (7.1.4 / 11.5) -->
+      <ContentPage Header="Briefvorlagen">
+        <ScrollViewer>
+          <StackPanel Margin="32,20,32,28" Spacing="16" MaxWidth="760">
+            <TextBlock Text="Word-Vorlagen bleiben vollständig in Word gestaltet. Die App befüllt Inhaltssteuerelemente anhand ihres Tags und prüft die Vorlage bereits beim Import."
+                       FontSize="12" Opacity="0.65" TextWrapping="Wrap"/>
+
+            <Grid ColumnDefinitions="Auto,*" ColumnSpacing="12">
+              <Button Grid.Column="0" Content="＋ DOCX-Vorlage importieren" Click="OnImportLetterTemplateClick"/>
+              <TextBlock Grid.Column="1" Text="{Binding LetterTemplateStatus}" FontSize="12"
+                         VerticalAlignment="Center" TextWrapping="Wrap"
+                         IsVisible="{Binding LetterTemplateStatus, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+            </Grid>
+
+            <TextBlock Text="Noch keine Briefvorlage importiert." Classes="emptyhint"
+                       IsVisible="{Binding !LetterTemplateList.Count}"/>
+
+            <ItemsControl ItemsSource="{Binding LetterTemplateList}">
+              <ItemsControl.ItemTemplate>
+                <DataTemplate DataType="vm:LetterTemplateListItem">
+                  <Border BorderBrush="{DynamicResource SystemControlForegroundBaseLowBrush}"
+                          BorderThickness="1" CornerRadius="7" Padding="14,12" Margin="0,0,0,9">
+                    <StackPanel Spacing="8">
+                      <Grid ColumnDefinitions="*,Auto,Auto,Auto">
+                        <StackPanel Grid.Column="0">
+                          <TextBlock Text="{Binding Name}" FontWeight="SemiBold" FontSize="14"/>
+                          <TextBlock FontSize="11" Opacity="0.55">
+                            <Run Text="{Binding OriginalFileName}"/><Run Text=" · "/>
+                            <Run Text="{Binding ValidationSummary}"/>
+                          </TextBlock>
+                        </StackPanel>
+                        <Button Grid.Column="1" Content="Öffnen" FontSize="12" Padding="10,4"
+                                Margin="8,0,0,0" Tag="{Binding}" Click="OnOpenLetterTemplateClick"/>
+                        <Button Grid.Column="2" Content="Neu prüfen" FontSize="12" Padding="10,4"
+                                Margin="8,0,0,0"
+                                Command="{Binding $parent[ItemsControl].((vm:SettingsViewModel)DataContext).ValidateLetterTemplateCommand}"
+                                CommandParameter="{Binding}"/>
+                        <Button Grid.Column="3" Content="Löschen" FontSize="12" Padding="10,4"
+                                Margin="8,0,0,0"
+                                Command="{Binding $parent[ItemsControl].((vm:SettingsViewModel)DataContext).DeleteLetterTemplateCommand}"
+                                CommandParameter="{Binding}"/>
+                      </Grid>
+
+                      <ItemsControl ItemsSource="{Binding Issues}" IsVisible="{Binding HasIssues}">
+                        <ItemsControl.ItemTemplate>
+                          <DataTemplate DataType="vm:LetterTemplateIssueItem">
+                            <Grid ColumnDefinitions="24,*" Margin="0,2">
+                              <TextBlock Grid.Column="0" Text="{Binding Icon}" Foreground="{Binding Color}"/>
+                              <TextBlock Grid.Column="1" Text="{Binding Message}" Foreground="{Binding Color}"
+                                         FontSize="12" TextWrapping="Wrap"/>
+                            </Grid>
+                          </DataTemplate>
+                        </ItemsControl.ItemTemplate>
+                      </ItemsControl>
+                      <TextBlock Text="✓ Vorlage ohne Auffälligkeiten" Foreground="SeaGreen" FontSize="12"
+                                 IsVisible="{Binding HasNoIssues}"/>
+                    </StackPanel>
+                  </Border>
+                </DataTemplate>
+              </ItemsControl.ItemTemplate>
+            </ItemsControl>
+
+            <Separator/>
+            <TextBlock Text="Unterstützte Tags" FontSize="15" FontWeight="SemiBold"/>
+            <TextBlock Text="In Word: Entwicklertools → Rich-Text- oder Nur-Text-Inhaltssteuerelement → Eigenschaften → Tag. Der Titel ist frei wählbar; ausgewertet wird der Tag."
+                       FontSize="12" Opacity="0.65" TextWrapping="Wrap"/>
+            <ItemsControl ItemsSource="{Binding SupportedLetterPlaceholders}">
+              <ItemsControl.ItemTemplate>
+                <DataTemplate DataType="services:LetterPlaceholder">
+                  <Grid ColumnDefinitions="190,*" Margin="0,3">
+                    <TextBlock Grid.Column="0" Text="{Binding Tag}" FontFamily="Monospace" FontSize="12"/>
+                    <TextBlock Grid.Column="1" Text="{Binding Description}" FontSize="12" Opacity="0.7"/>
+                  </Grid>
+                </DataTemplate>
+              </ItemsControl.ItemTemplate>
+            </ItemsControl>
+          </StackPanel>
+        </ScrollViewer>
+      </ContentPage>
+
      <!-- Tab: Notenschema -->
      <ContentPage Header="Notenschema">
        <ContentPage.Resources>
@@ -91,4 +91,27 @@ public partial class SettingsView : UserControl
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog(owner);
    }
+
+    private async void OnImportLetterTemplateClick(object? sender, RoutedEventArgs e)
+    {
+        var topLevel = TopLevel.GetTopLevel(this);
+        if (topLevel is null || DataContext is not SettingsViewModel vm) return;
+
+        var files = await topLevel.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
+        {
+            Title = "Word-Briefvorlage importieren",
+            AllowMultiple = false,
+            FileTypeFilter = [new FilePickerFileType("Word-Dokumente") { Patterns = ["*.docx"] }],
+        });
+        if (files.Count > 0) vm.ImportLetterTemplate(files[0].Path.LocalPath);
+    }
+
+    private void OnOpenLetterTemplateClick(object? sender, RoutedEventArgs e)
+    {
+        if (sender is not Button { Tag: LetterTemplateListItem item }) return;
+        var service = App.Services.GetRequiredService<LehrerApp.Core.Services.LetterTemplateService>();
+        var path = service.GetTemplatePath(item.Model);
+        if (!File.Exists(path)) return;
+        System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(path) { UseShellExecute = true });
+    }
 }
@@ -72,6 +72,9 @@
                      <Button Grid.Column="4" Content="×" Padding="6,2"
                              Command="{Binding RemoveCommand}" FontSize="14"/>
                    </Grid>
+                    <TextBox Text="{Binding LetterSalutation}"
+                             PlaceholderText="Briefanrede, z.B. Sehr geehrte Frau Mustermann,"
+                             FontSize="12"/>
                    <!-- Zeile 2: Telefon + E-Mail -->
                    <Grid ColumnDefinitions="*,10,*">
                      <TextBox Grid.Column="0" Text="{Binding Phone}"
@@ -28,6 +28,14 @@
          </StackPanel>
        </Grid>

+        <StackPanel Spacing="4">
+          <TextBlock Text="Briefanrede" FontSize="12" Opacity="0.7"/>
+          <TextBox Text="{Binding LetterSalutation}"
+                   PlaceholderText="z.B. Sehr geehrte Frau Mustermann,"/>
+          <TextBlock Text="Wird unverändert in Word-Vorlagen für Letter.Salutation eingesetzt."
+                     FontSize="11" Opacity="0.55" TextWrapping="Wrap"/>
+        </StackPanel>
+
        <Grid ColumnDefinitions="*,10,*">
          <StackPanel Grid.Column="0" Spacing="4">
            <TextBlock Text="Telefon" FontSize="12" Opacity="0.7"/>
@@ -0,0 +1,75 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Students"
+        x:Class="LehrerApp.Desktop.Views.Students.CreateLetterDialog"
+        x:DataType="vm:CreateLetterDialogViewModel"
+        Title="Word-Brief erstellen" Width="580" Height="650"
+        MinWidth="500" MinHeight="540" CanResize="True"
+        WindowStartupLocation="CenterOwner">
+  <Grid RowDefinitions="*,Auto" Margin="24,20">
+    <ScrollViewer Grid.Row="0" VerticalScrollBarVisibility="Auto">
+      <StackPanel Spacing="15">
+        <TextBlock Text="Word-Brief erstellen" Classes="dialogtitle"/>
+        <TextBlock FontSize="12" Opacity="0.65" TextWrapping="Wrap"
+                   Text="Die Vorlage wird vor der Erzeugung erneut geprüft. Das Original bleibt unverändert; gespeichert wird eine frei bearbeitbare DOCX-Kopie."/>
+
+        <StackPanel Spacing="4">
+          <TextBlock Text="Schüler" FontSize="12" Opacity="0.7"/>
+          <TextBlock Text="{Binding StudentName}" FontWeight="SemiBold"/>
+        </StackPanel>
+        <StackPanel Spacing="4">
+          <TextBlock Text="Vorlage *" FontSize="12" Opacity="0.7"/>
+          <ComboBox ItemsSource="{Binding Templates}" SelectedItem="{Binding SelectedTemplate}"
+                    DisplayMemberBinding="{Binding Name}" HorizontalAlignment="Stretch"/>
+          <TextBlock Text="Noch keine Vorlage. Bitte unter Einstellungen → Briefvorlagen importieren."
+                     Classes="emptyhint" IsVisible="{Binding HasNoTemplates}"/>
+        </StackPanel>
+        <StackPanel Spacing="4">
+          <TextBlock Text="Kontakt *" FontSize="12" Opacity="0.7"/>
+          <ComboBox ItemsSource="{Binding Contacts}" SelectedItem="{Binding SelectedContact}"
+                    DisplayMemberBinding="{Binding Display}" HorizontalAlignment="Stretch"/>
+          <TextBlock Text="Kein aktueller Kontakt vorhanden." Classes="emptyhint"
+                     IsVisible="{Binding HasNoContacts}"/>
+        </StackPanel>
+        <Grid ColumnDefinitions="*,12,*">
+          <StackPanel Grid.Column="0" Spacing="4">
+            <TextBlock Text="Lerngruppe" FontSize="12" Opacity="0.7"/>
+            <ComboBox ItemsSource="{Binding Groups}" SelectedItem="{Binding SelectedGroup}"
+                      DisplayMemberBinding="{Binding Display}" PlaceholderText="Optional"
+                      HorizontalAlignment="Stretch"/>
+          </StackPanel>
+          <StackPanel Grid.Column="2" Spacing="4">
+            <TextBlock Text="Briefdatum *" FontSize="12" Opacity="0.7"/>
+            <CalendarDatePicker SelectedDate="{Binding LetterDate}" HorizontalAlignment="Stretch"/>
+          </StackPanel>
+        </Grid>
+
+        <Border BorderBrush="#D97706" BorderThickness="1" CornerRadius="6" Padding="10"
+                IsVisible="{Binding HasIssues}">
+          <StackPanel Spacing="5">
+            <TextBlock Text="Vor dem Erzeugen korrigieren" FontWeight="SemiBold" Foreground="#D97706"/>
+            <ItemsControl ItemsSource="{Binding Issues}">
+              <ItemsControl.ItemTemplate>
+                <DataTemplate x:DataType="vm:LetterGenerationIssue">
+                  <Grid ColumnDefinitions="24,*" Margin="0,2">
+                    <TextBlock Grid.Column="0" Text="{Binding Icon}" Foreground="{Binding Color}"/>
+                    <TextBlock Grid.Column="1" Text="{Binding Message}" Foreground="{Binding Color}"
+                               FontSize="12" TextWrapping="Wrap"/>
+                  </Grid>
+                </DataTemplate>
+              </ItemsControl.ItemTemplate>
+            </ItemsControl>
+          </StackPanel>
+        </Border>
+        <TextBlock Text="{Binding GenerationError}" Foreground="Red" FontSize="12" TextWrapping="Wrap"
+                   IsVisible="{Binding GenerationError, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+      </StackPanel>
+    </ScrollViewer>
+
+    <Grid Grid.Row="1" ColumnDefinitions="*,10,*" Margin="0,18,0,0">
+      <Button Grid.Column="0" Content="Abbrechen" HorizontalAlignment="Stretch" Click="OnCancel"/>
+      <Button Grid.Column="2" Content="DOCX speichern …" HorizontalAlignment="Stretch"
+              IsEnabled="{Binding CanGenerate}" Click="OnGenerate"/>
+    </Grid>
+  </Grid>
+</Window>
@@ -0,0 +1,27 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Platform.Storage;
+using LehrerApp.Desktop.ViewModels.Students;
+
+namespace LehrerApp.Desktop.Views.Students;
+
+public partial class CreateLetterDialog : Window
+{
+    public CreateLetterDialog() => InitializeComponent();
+
+    private async void OnGenerate(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not CreateLetterDialogViewModel vm) return;
+        var file = await StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
+        {
+            Title = "Word-Brief speichern",
+            SuggestedFileName = vm.SuggestedFileName,
+            DefaultExtension = "docx",
+            FileTypeChoices = [new FilePickerFileType("Word-Dokumente") { Patterns = ["*.docx"] }],
+        });
+        if (file is null || !vm.Generate(file.Path.LocalPath)) return;
+        Close(file.Path.LocalPath);
+    }
+
+    private void OnCancel(object? sender, RoutedEventArgs e) => Close(null);
+}
@@ -0,0 +1,59 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Students"
+        x:Class="LehrerApp.Desktop.Views.Students.ManageStudentDialog"
+        x:DataType="vm:ManageStudentDialogViewModel"
+        Title="Schüler verwalten"
+        Width="500" Height="500"
+        CanResize="False" WindowStartupLocation="CenterOwner">
+
+  <Grid RowDefinitions="*,Auto" Margin="24">
+    <StackPanel Grid.Row="0" Spacing="14">
+      <TextBlock Text="Schüler verwalten" Classes="dialogtitle"/>
+      <TextBlock Text="{Binding StudentName}" FontSize="15" FontWeight="SemiBold"/>
+
+      <Border Background="{DynamicResource SystemControlBackgroundAltHighBrush}"
+              CornerRadius="6" Padding="14">
+        <StackPanel Spacing="8">
+          <TextBlock Text="Deaktivieren blendet den Schüler aus den normalen Listen aus. Alle historischen Daten bleiben erhalten."
+                     TextWrapping="Wrap" FontSize="12"/>
+          <TextBlock Text="Der Schüler ist bereits deaktiviert und kann wieder aktiviert werden."
+                     TextWrapping="Wrap" FontSize="12" IsVisible="{Binding IsInactive}"/>
+        </StackPanel>
+      </Border>
+
+      <StackPanel Spacing="8" IsVisible="{Binding HasReferences}">
+        <TextBlock Text="Verknüpfte Daten" FontWeight="SemiBold"/>
+        <ItemsControl ItemsSource="{Binding ReferenceItems}">
+          <ItemsControl.ItemTemplate>
+            <DataTemplate x:DataType="vm:StudentReferenceItem">
+              <Grid ColumnDefinitions="*,Auto" Margin="0,2">
+                <TextBlock Grid.Column="0" Text="{Binding Label}"/>
+                <TextBlock Grid.Column="1" Text="{Binding CountDisplay}" FontWeight="SemiBold"/>
+              </Grid>
+            </DataTemplate>
+          </ItemsControl.ItemTemplate>
+        </ItemsControl>
+        <TextBlock Text="Eine endgültige Löschung ist deshalb gesperrt. Verwende stattdessen Deaktivieren."
+                   Foreground="#D97706" TextWrapping="Wrap" FontSize="12"/>
+      </StackPanel>
+
+      <Border IsVisible="{Binding CanDelete}" BorderBrush="#C62828" BorderThickness="1"
+              CornerRadius="6" Padding="12">
+        <TextBlock Text="Es bestehen keine Verknüpfungen. Der Schüler kann endgültig gelöscht werden. Stammdaten und Kontakte gehen dabei unwiderruflich verloren."
+                   Foreground="#C62828" TextWrapping="Wrap" FontSize="12"/>
+      </Border>
+
+      <TextBlock Text="{Binding ErrorMessage}" Foreground="Red" FontSize="12"
+                 IsVisible="{Binding ErrorMessage, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+    </StackPanel>
+
+    <Grid Grid.Row="1" ColumnDefinitions="Auto,Auto,*,Auto" ColumnSpacing="8" Margin="0,18,0,0">
+      <Button Grid.Column="0" Content="Deaktivieren" Click="OnDeactivate" IsVisible="{Binding IsActive}"/>
+      <Button Grid.Column="0" Content="Wieder aktivieren" Click="OnReactivate" IsVisible="{Binding IsInactive}"/>
+      <Button Grid.Column="1" Content="Endgültig löschen" Click="OnDeletePermanently"
+              IsEnabled="{Binding CanDelete}"/>
+      <Button Grid.Column="3" Content="Schließen" Click="OnCancel"/>
+    </Grid>
+  </Grid>
+</Window>
@@ -0,0 +1,33 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using LehrerApp.Desktop.ViewModels.Students;
+
+namespace LehrerApp.Desktop.Views.Students;
+
+public partial class ManageStudentDialog : Window
+{
+    public ManageStudentDialog() => InitializeComponent();
+
+    private void OnDeactivate(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not ManageStudentDialogViewModel vm) return;
+        vm.DeactivateCommand.Execute(null);
+        Close(vm.Result);
+    }
+
+    private void OnReactivate(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not ManageStudentDialogViewModel vm) return;
+        vm.ReactivateCommand.Execute(null);
+        Close(vm.Result);
+    }
+
+    private void OnDeletePermanently(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is not ManageStudentDialogViewModel vm) return;
+        vm.DeletePermanentlyCommand.Execute(null);
+        if (vm.Result == StudentManagementResult.Deleted) Close(vm.Result);
+    }
+
+    private void OnCancel(object? sender, RoutedEventArgs e) => Close(StudentManagementResult.Cancelled);
+}
@@ -11,16 +11,29 @@
            BorderBrush="{DynamicResource SystemControlForegroundBaseLowBrush}"
            BorderThickness="0,0,0,1">
      <Grid ColumnDefinitions="*,Auto">
-        <shared:PageHeader Grid.Column="0" IsVisible="{Binding !IsEditing}" Title="{Binding StudentTitle}"/>
+        <Border Grid.Column="0" Width="38" Height="38" CornerRadius="19"
+                Background="{Binding StudentAvatarColor}" HorizontalAlignment="Left"
+                ToolTip.Tip="{Binding StudentAvatarTooltip}" IsVisible="{Binding !IsEditing}">
+          <TextBlock Text="{Binding StudentAvatarLabel}" Foreground="White" FontWeight="Bold" FontSize="15"
+                     HorizontalAlignment="Center" VerticalAlignment="Center"/>
+        </Border>
+        <shared:PageHeader Grid.Column="0" Margin="50,0,0,0" IsVisible="{Binding !IsEditing}" Title="{Binding StudentTitle}"/>
        <StackPanel Grid.Column="0" Spacing="6" IsVisible="{Binding IsEditing}">
-          <Grid ColumnDefinitions="*,8,*">
+          <Grid ColumnDefinitions="*,8,*,8,170">
            <TextBox Grid.Column="0" Text="{Binding EditFirstName}" PlaceholderText="Vorname"/>
            <TextBox Grid.Column="2" Text="{Binding EditLastName}"  PlaceholderText="Nachname"/>
+            <ComboBox Grid.Column="4" ItemsSource="{Binding GenderOptions}"
+                      SelectedItem="{Binding EditGender}" PlaceholderText="Geschlecht"/>
          </Grid>
        </StackPanel>
        <StackPanel Grid.Column="1" Orientation="Horizontal" Spacing="8" VerticalAlignment="Top">
+          <TextBlock Text="{Binding StudentStatus}" VerticalAlignment="Center" Opacity="0.65"/>
+          <Button Content="Word-Brief" Command="{Binding CreateLetterCommand}"
+                  IsVisible="{Binding !IsEditing}"/>
          <Button Content="Bearbeiten" Command="{Binding StartEditCommand}"
                  IsVisible="{Binding !IsEditing}"/>
+          <Button Content="Schüler verwalten" Command="{Binding ManageStudentCommand}"
+                  IsVisible="{Binding !IsEditing}"/>
          <Button Content="Speichern"  Command="{Binding SaveEditCommand}"
                  IsVisible="{Binding IsEditing}"/>
          <Button Content="Abbrechen"  Command="{Binding CancelEditCommand}"
@@ -88,6 +101,9 @@
                                CornerRadius="4" Padding="6,2" HorizontalAlignment="Left">
                          <TextBlock Text="{Binding Relation}" FontSize="11" Opacity="0.7"/>
                        </Border>
+                        <TextBlock Text="{Binding LetterSalutation}" FontSize="11" Opacity="0.6"
+                                   TextWrapping="Wrap"
+                                   IsVisible="{Binding LetterSalutation, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
                      </StackPanel>

                      <StackPanel Grid.Column="1" Grid.Row="0" Orientation="Horizontal" Spacing="8">
@@ -23,6 +23,8 @@ public partial class StudentDetailView : UserControl
        vm.OnConfirmDeleteDocumentation = ShowDeleteDocumentationDialog;
        vm.OnSaveExportFile = SaveExportFile;
        vm.OnConductParentCall = ShowParentCallSessionDialog;
+        vm.OnManageStudent = ShowManageStudentDialog;
+        vm.OnCreateLetter = ShowCreateLetterDialog;
    }

    private async Task<Contact?> ShowContactDialog(Contact? contact)
@@ -36,6 +38,32 @@ public partial class StudentDetailView : UserControl
        return saved ? vm.Result : null;
    }

+    private async Task<StudentManagementResult> ShowManageStudentDialog(Student student)
+    {
+        var owner = TopLevel.GetTopLevel(this) as Window;
+        if (owner is null) return StudentManagementResult.Cancelled;
+
+        var vm = new ManageStudentDialogViewModel(
+            App.Services.GetRequiredService<IStudentRepository>(), student);
+        var dialog = new ManageStudentDialog { DataContext = vm };
+        return await dialog.ShowDialog<StudentManagementResult>(owner);
+    }
+
+    private async Task ShowCreateLetterDialog()
+    {
+        var owner = TopLevel.GetTopLevel(this) as Window;
+        if (owner is null || DataContext is not StudentDetailViewModel { Student: { } student }) return;
+
+        var vm = new CreateLetterDialogViewModel(student,
+            App.Services.GetRequiredService<LehrerApp.Core.Services.LetterTemplateService>(),
+            App.Services.GetRequiredService<IGroupMembershipRepository>(),
+            App.Services.GetRequiredService<IGroupRepository>());
+        var dialog = new CreateLetterDialog { DataContext = vm };
+        var path = await dialog.ShowDialog<string?>(owner);
+        if (!string.IsNullOrEmpty(path) && File.Exists(path))
+            System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(path) { UseShellExecute = true });
+    }
+
    private void ShowAddressViewer(ContactItem contact)
    {
        if (!contact.HasAddress) return;
@@ -19,13 +19,25 @@
    </Border>
    <DockPanel Grid.Row="1">
      <TextBox DockPanel.Dock="Top" Text="{Binding SearchText}"
-               PlaceholderText="Name suchen…" Margin="16,10,16,4"/>
+               PlaceholderText="Name oder Lerngruppe suchen…" Margin="16,10,16,4"/>
      <DataGrid ItemsSource="{Binding Students}"
                SelectedItem="{Binding SelectedStudent}"
                AutoGenerateColumns="False" IsReadOnly="True"
                GridLinesVisibility="Horizontal"
                CanUserReorderColumns="False" Margin="16,4">
        <DataGrid.Columns>
+          <DataGridTemplateColumn Header="" Width="48">
+            <DataGridTemplateColumn.CellTemplate>
+              <DataTemplate x:DataType="vm:StudentListItem">
+                <Border Width="30" Height="30" CornerRadius="15" Background="{Binding AvatarColor}"
+                        HorizontalAlignment="Center" VerticalAlignment="Center"
+                        ToolTip.Tip="{Binding AvatarTooltip}">
+                  <TextBlock Text="{Binding AvatarLabel}" Foreground="White" FontWeight="Bold"
+                             HorizontalAlignment="Center" VerticalAlignment="Center"/>
+                </Border>
+              </DataTemplate>
+            </DataGridTemplateColumn.CellTemplate>
+          </DataGridTemplateColumn>
          <DataGridTextColumn Header="Name"         Binding="{Binding FullName}"    Width="*"/>
          <DataGridTextColumn Header="Geburtsdatum" Binding="{Binding DateOfBirth}" Width="130"/>
        </DataGrid.Columns>