diff --git a/LehrerApp.Core/Models/Participation.cs b/LehrerApp.Core/Models/Participation.cs
index af32d6a..45be265 100644
--- a/LehrerApp.Core/Models/Participation.cs
+++ b/LehrerApp.Core/Models/Participation.cs
@@ -32,9 +32,18 @@ public class ParticipationEntry
     // ParticipationCountSuggestion.
     public int RaisedHandCount { get; set; }
     public int CalledOnCount { get; set; }
+    /// <summary>
+    /// Tagesflagge (Nutzer-Feedback): markiert eine session-bezogene Bewertung als besonders
+    /// herausragend oder besonders schwach, unabhängig von der Richtung ("egal in welche
+    /// Richtung, herausragend festhalten"). Rein deskriptiv — fließt nirgends in eine Berechnung
+    /// (Mitarbeitsnote 3.2, Aufrufgerechtigkeit) ein, nur zur Erinnerung/Dokumentation.
+    /// </summary>
+    public DayHighlightKind? DayHighlight { get; set; }
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
 }
 
+public enum DayHighlightKind { Standout, Sleepy, Rough }
+
 /// <summary>
 /// Hausaufgabenstatus einer Sitzung; null bedeutet, dass für diesen Termin keine
 /// Hausaufgabe erfasst wurde. MissingOpen kann später in MissingOverdue oder SubmittedLate
diff --git a/LehrerApp.Core/Services/ReportGradeTargetCalculator.cs b/LehrerApp.Core/Services/ReportGradeTargetCalculator.cs
new file mode 100644
index 0000000..ecce664
--- /dev/null
+++ b/LehrerApp.Core/Services/ReportGradeTargetCalculator.cs
@@ -0,0 +1,48 @@
+using LehrerApp.Core.Models;
+
+namespace LehrerApp.Core.Services;
+
+/// Welcher der drei Leistungsbereiche (siehe GradingScheme) bei der Zielnoten-Frage der
+/// gesuchte/unbekannte ist.
+public enum GradeBucketKind { Exams, Participation, Other }
+
+public readonly record struct TargetGradeResult(double RequiredAverage, bool IsAchievable);
+
+/// <summary>
+/// Beantwortet die Zielnoten-Frage "Was brauche ich noch, um Zeugnisnote X zu erreichen?"
+/// (Nutzer-Feedback) — kehrt <see cref="GradingService.CalculateReportGrade"/> um: löst nach
+/// dem Durchschnitt eines gewählten Bereichs auf, der zusammen mit den bekannten Durchschnitten
+/// der übrigen Bereiche (gewichtet nach <see cref="GradingScheme"/>) genau die Zielnote ergibt.
+/// Bereiche ohne bekannten Durchschnitt (z.B. noch keine Mitarbeitsnote im Halbjahr) fließen
+/// nicht in die bekannte Seite der Gleichung ein — exakt dieselbe Normierung wie
+/// <see cref="GradingService.CalculateReportGrade"/> bei fehlenden Bereichen.
+/// </summary>
+public static class ReportGradeTargetCalculator
+{
+    public static TargetGradeResult? SolveRequiredAverage(double target, GradeBucketKind solveFor,
+        double? examsAverage, double? participationAverage, double? otherAverage,
+        GradingScheme scheme, GradingSystem system)
+    {
+        var solvePercent = solveFor switch
+        {
+            GradeBucketKind.Exams => scheme.ExamsPercent,
+            GradeBucketKind.Participation => scheme.ParticipationPercent,
+            _ => scheme.OtherPercent,
+        };
+        // Dieser Bereich fließt laut Gewichtungsschema gar nicht in die Zeugnisnote ein —
+        // keine Zielnoten-Frage für ihn beantwortbar.
+        if (solvePercent <= 0) return null;
+
+        var known = new List<(double Avg, double Percent)>();
+        if (solveFor != GradeBucketKind.Exams && examsAverage is { } e) known.Add((e, scheme.ExamsPercent));
+        if (solveFor != GradeBucketKind.Participation && participationAverage is { } p) known.Add((p, scheme.ParticipationPercent));
+        if (solveFor != GradeBucketKind.Other && otherAverage is { } o) known.Add((o, scheme.OtherPercent));
+
+        var totalPercent = known.Sum(k => k.Percent) + solvePercent;
+        var knownContribution = known.Sum(k => k.Avg * k.Percent);
+        var required = (target * totalPercent - knownContribution) / solvePercent;
+
+        var (min, max) = system == GradingSystem.Grades1To6 ? (1.0, 6.0) : (0.0, 15.0);
+        return new TargetGradeResult(required, required >= min && required <= max);
+    }
+}
diff --git a/LehrerApp.Desktop.Tests/QuickInputViewModelTests.cs b/LehrerApp.Desktop.Tests/QuickInputViewModelTests.cs
index fca4c2d..12683d0 100644
--- a/LehrerApp.Desktop.Tests/QuickInputViewModelTests.cs
+++ b/LehrerApp.Desktop.Tests/QuickInputViewModelTests.cs
@@ -103,6 +103,47 @@ public sealed class QuickInputViewModelTests
         Assert.Null(rows[0].GetRating("quality"));
     }
 
+    [Fact]
+    public void SetDayHighlight_SpeichertAufDerZeileUndAktualisiertDieAnzeige()
+    {
+        var aspects = new List<AspectColumnDef>
+        {
+            new(new ParticipationAspect { Key = "quality", Label = "Qualität" }),
+        };
+        var rows = new List<ParticipationStudentRow>
+        {
+            new(Guid.NewGuid(), "Anna", new ParticipationEntry(), aspects, []),
+        };
+        var vm = new QuickInputViewModel(rows, aspects);
+
+        vm.SetDayHighlight(DayHighlightKind.Standout);
+
+        Assert.Equal(DayHighlightKind.Standout, rows[0].DayHighlight);
+        Assert.Equal("👑", vm.CurrentStudentDayHighlightSymbol);
+        Assert.Equal("Spitzentag", vm.CurrentStudentDayHighlightLabel);
+    }
+
+    [Fact]
+    public void ZurueckZuVorherigemSchueler_ZeigtDessenTagesflaggeWiederAn()
+    {
+        var aspects = new List<AspectColumnDef>
+        {
+            new(new ParticipationAspect { Key = "quality", Label = "Qualität" }),
+        };
+        var rows = new List<ParticipationStudentRow>
+        {
+            new(Guid.NewGuid(), "Anna", new ParticipationEntry(), aspects, []),
+            new(Guid.NewGuid(), "Ben", new ParticipationEntry(), aspects, []),
+        };
+        var vm = new QuickInputViewModel(rows, aspects);
+
+        vm.SetDayHighlight(DayHighlightKind.Sleepy); // Anna
+        vm.NextStudent();                            // zu Ben, keine Flagge
+        vm.PreviousStudent();                        // zurück zu Anna
+
+        Assert.Equal(DayHighlightKind.Sleepy, vm.CurrentStudentDayHighlight);
+    }
+
     [Fact]
     public void VorherigerAspekt_SpringtRueckwaertsMitUmlauf()
     {
diff --git a/LehrerApp.Desktop.Tests/SeatingPlanViewModelTests.cs b/LehrerApp.Desktop.Tests/SeatingPlanViewModelTests.cs
index 46c06f7..2f748be 100644
--- a/LehrerApp.Desktop.Tests/SeatingPlanViewModelTests.cs
+++ b/LehrerApp.Desktop.Tests/SeatingPlanViewModelTests.cs
@@ -472,6 +472,7 @@ public sealed class SeatingPlanViewModelTests
         vm.SetRatingByNumber(5);
         vm.ApplyAttendanceShortcut(1, clear: false);
         vm.ApplyHomeworkShortcut(7, clear: false);
+        vm.ApplyDayHighlightShortcut(1, clear: false);
 
         var session = Assert.Single(sessions.GetByGroup(groupId));
         Assert.Equal(DateOnly.FromDateTime(DateTime.Today), session.Date);
@@ -481,6 +482,27 @@ public sealed class SeatingPlanViewModelTests
         Assert.Equal(AttendanceStatus.Present, entry.Attendance);
         Assert.Equal(HomeworkStatus.MissingOpen, entry.Homework);
         Assert.True(entry.HomeworkMissing);
+        Assert.Equal(DayHighlightKind.Standout, entry.DayHighlight);
+    }
+
+    [Fact]
+    public void SitzplatzBewertung_TagesflaggeKannWiederGeloeschtWerden()
+    {
+        var groupId = Guid.NewGuid();
+        var studentId = Guid.NewGuid();
+        var sessions = new FakeSessions([]);
+        var entries = new FakeEntries();
+        var vm = new SeatAssessmentViewModel(sessions, entries, new FakeAspects(),
+            groupId, studentId, "Beispiel, Anna", canEdit: true);
+
+        vm.ApplyDayHighlightShortcut(3, clear: false); // aus Versehen "Schlechter Tag" gesetzt
+        vm.ApplyDayHighlightShortcut(null, clear: true);
+
+        var session = Assert.Single(sessions.GetByGroup(groupId));
+        var entry = entries.GetBySessionAndStudent(session.Id, studentId)!;
+        Assert.Null(entry.DayHighlight);
+        Assert.Equal("Keine Markierung", vm.DayHighlightLabel);
+        Assert.All(vm.DayHighlightChoices, c => Assert.Equal(c.Kind is null, c.IsSelected));
     }
 
     [Fact]
diff --git a/LehrerApp.Desktop.Tests/StudentPerformanceOverviewViewModelTests.cs b/LehrerApp.Desktop.Tests/StudentPerformanceOverviewViewModelTests.cs
new file mode 100644
index 0000000..b2b6328
--- /dev/null
+++ b/LehrerApp.Desktop.Tests/StudentPerformanceOverviewViewModelTests.cs
@@ -0,0 +1,146 @@
+using LehrerApp.Core.Models;
+using LehrerApp.Core.Services;
+using LehrerApp.Desktop.ViewModels.Groups;
+using Xunit;
+
+namespace LehrerApp.Desktop.Tests;
+
+/// Tests für den Schüler-Leistungsüberblick (Nutzer-Feedback): Klausuren/Mitarbeit/Sonstige
+/// im Überblick, berechnete Zeugnisnote, Zielnoten- und Was-wäre-wenn-Rechner sowie der
+/// Bewerter-/Schülermodus-Unterschied (Kursdurchschnitt, Bearbeitbarkeit).
+public sealed class StudentPerformanceOverviewViewModelTests
+{
+    private static readonly Guid GroupId = Guid.NewGuid();
+    private static readonly Guid StudentId = Guid.NewGuid();
+    private static readonly Guid OtherStudentId = Guid.NewGuid();
+
+    private static StudentPerformanceOverviewViewModel BuildViewModel(
+        FakeExams? exams = null, FakeResults? results = null, FakeGrades? grades = null,
+        FakeSchemes? schemes = null, GradingSystem system = GradingSystem.Grades1To6)
+    {
+        var scheme = new GradingScheme { ExamsPercent = 50, ParticipationPercent = 40, OtherPercent = 10 };
+        var schemesRepo = schemes ?? new FakeSchemes();
+        if (schemes is null) schemesRepo.SetForGroup(GroupId, scheme);
+
+        return new StudentPerformanceOverviewViewModel(
+            grades ?? new FakeGrades(), exams ?? new FakeExams([]), results ?? new FakeResults(),
+            new FakeMemberships([]), schemesRepo, new GradingService(),
+            GroupId, StudentId, GroupType.Class, system, "Beispiel, Anna", "Testkurs", "2025/26");
+    }
+
+    [Fact]
+    public void ExamRows_ZeigtEigeneNoteUndKursdurchschnitt()
+    {
+        var exam = new Exam { Id = Guid.NewGuid(), GroupId = GroupId, Title = "K1", Date = new DateOnly(2025, 9, 10) };
+        var exams = new FakeExams([exam]);
+        var results = new FakeResults();
+        results.Add(new ExamResult { ExamId = exam.Id, StudentId = StudentId, Grade = "2" });
+        results.Add(new ExamResult { ExamId = exam.Id, StudentId = OtherStudentId, Grade = "4" });
+
+        var vm = BuildViewModel(exams, results);
+
+        var row = Assert.Single(vm.ExamRows);
+        Assert.Equal("2", row.OwnGradeDisplay);
+        Assert.Equal("3.0", row.ClassAverageDisplay);
+    }
+
+    [Fact]
+    public void ExamHistory_ZeigtEigenenVerlaufUndMarkiertNotenabfall()
+    {
+        var exam1 = new Exam { Id = Guid.NewGuid(), GroupId = GroupId, Title = "K1", Date = new DateOnly(2025, 9, 10) };
+        var exam2 = new Exam { Id = Guid.NewGuid(), GroupId = GroupId, Title = "K2", Date = new DateOnly(2025, 9, 24) };
+        var exams = new FakeExams([exam1, exam2]);
+        var results = new FakeResults();
+        results.Add(new ExamResult { ExamId = exam1.Id, StudentId = StudentId, Grade = "2" });
+        results.Add(new ExamResult { ExamId = exam2.Id, StudentId = StudentId, Grade = "5" }); // Abfall + mangelhaft
+
+        var vm = BuildViewModel(exams, results);
+
+        Assert.Equal(2, vm.ExamHistory.Points.Count);
+        Assert.False(vm.ExamHistory.Points[0].IsWarning);
+        Assert.True(vm.ExamHistory.Points[1].IsWarning);
+        Assert.Contains("Abfall", vm.ExamHistory.Points[1].WarningText);
+        Assert.Contains("Versetzungsgefährdung", vm.ExamHistory.Points[1].WarningText);
+        Assert.True(vm.ExamHistory.Points[1].BarHeight < vm.ExamHistory.Points[0].BarHeight);
+    }
+
+    [Fact]
+    public void AktuelleZeugnisnote_KombiniertAlleDreiBereiche()
+    {
+        var exam = new Exam { Id = Guid.NewGuid(), GroupId = GroupId, Title = "K1", Date = new DateOnly(2025, 9, 10) };
+        var exams = new FakeExams([exam]);
+        var results = new FakeResults();
+        results.Add(new ExamResult { ExamId = exam.Id, StudentId = StudentId, Grade = "2" });
+        var grades = new FakeGrades();
+        grades.Add(new Grade { StudentId = StudentId, GroupId = GroupId, Category = GradeCategory.Participation,
+            Date = new DateOnly(2025, 9, 5), Value = "3" });
+        grades.Add(new Grade { StudentId = StudentId, GroupId = GroupId, Category = GradeCategory.Other,
+            Date = new DateOnly(2025, 9, 5), Value = "1" });
+
+        var vm = BuildViewModel(exams, results, grades);
+
+        // (2*50 + 3*40 + 1*10) / 100 = 2.3 -> kaufmännisch 2
+        Assert.Equal("Note 2", vm.CurrentReportGradeDisplay);
+    }
+
+    [Fact]
+    public void Zielnote_BerechnetNoetigenKlausurschnitt()
+    {
+        var grades = new FakeGrades();
+        grades.Add(new Grade { StudentId = StudentId, GroupId = GroupId, Category = GradeCategory.Participation,
+            Date = new DateOnly(2025, 9, 5), Value = "3" });
+        grades.Add(new Grade { StudentId = StudentId, GroupId = GroupId, Category = GradeCategory.Other,
+            Date = new DateOnly(2025, 9, 5), Value = "2" });
+        var vm = BuildViewModel(grades: grades);
+
+        vm.TargetGradeText = "2";
+        vm.TargetBucketName = "Klausuren";
+
+        // Ziel 2,0 = (x*50 + 3*40 + 2*10)/100 => 200 = 50x+120+20 => x = 1,2
+        Assert.Contains("1.2", vm.TargetResultDisplay);
+    }
+
+    [Fact]
+    public void WasWaereWenn_ZeigtZeugnisnoteMitZusaetzlicherKlausurAn()
+    {
+        var exam = new Exam { Id = Guid.NewGuid(), GroupId = GroupId, Title = "K1", Date = new DateOnly(2025, 9, 10) };
+        var exams = new FakeExams([exam]);
+        var results = new FakeResults();
+        results.Add(new ExamResult { ExamId = exam.Id, StudentId = StudentId, Grade = "2" });
+        var grades = new FakeGrades();
+        grades.Add(new Grade { StudentId = StudentId, GroupId = GroupId, Category = GradeCategory.Participation,
+            Date = new DateOnly(2025, 9, 5), Value = "2" });
+
+        var vm = BuildViewModel(exams, results, grades);
+
+        vm.WhatIfExamGradeText = "6";
+
+        // Klausuren neu: (2+6)/2=4 (50%), Mitarbeit 2 (40%, Sonstige fehlt) -> (4*50+2*40)/90 = 3,11 -> kaufm. 3
+        Assert.Contains("3", vm.WhatIfResultDisplay);
+    }
+
+    [Fact]
+    public void SaveCommand_AufMitarbeitszeile_SpeichertUndAktualisiertDurchschnitt()
+    {
+        var grades = new FakeGrades();
+        var grade = new Grade { StudentId = StudentId, GroupId = GroupId, Category = GradeCategory.Participation,
+            Date = new DateOnly(2025, 9, 5), Value = "3" };
+        grades.Add(grade);
+        var vm = BuildViewModel(grades: grades);
+
+        var row = Assert.Single(vm.ParticipationRows);
+        row.Value = "1";
+        row.SaveCommand.Execute(null);
+
+        Assert.Equal("1.0", vm.ParticipationAverageDisplay);
+        Assert.Equal("1", grades.GetByStudentAndGroup(StudentId, GroupId).Single().Value);
+    }
+
+    [Fact]
+    public void OhneWerteImZeitraum_ZeigtHinweisStattZeugnisnote()
+    {
+        var vm = BuildViewModel();
+
+        Assert.Contains("Noch nicht berechenbar", vm.CurrentReportGradeDisplay);
+    }
+}
diff --git a/LehrerApp.Desktop/ViewModels/Groups/GradeOverviewViewModels.cs b/LehrerApp.Desktop/ViewModels/Groups/GradeOverviewViewModels.cs
index 793b85a..29cc665 100644
--- a/LehrerApp.Desktop/ViewModels/Groups/GradeOverviewViewModels.cs
+++ b/LehrerApp.Desktop/ViewModels/Groups/GradeOverviewViewModels.cs
@@ -54,6 +54,7 @@ public partial class GradeOverviewTabViewModel : ObservableObject
     public Func<GradeOverviewRow, Task>? OnManageStudentGrades { get; set; }
     public Func<Task>? OnCollectiveGrade { get; set; }
     public Func<Task>? OnReportGrades { get; set; }
+    public Func<GradeOverviewRow, Task>? OnShowPerformanceOverview { get; set; }
 
     public GradeOverviewTabViewModel(IGradeRepository grades, IExamRepository exams,
         IExamResultRepository results, IStudentRepository students,
@@ -107,6 +108,14 @@ public partial class GradeOverviewTabViewModel : ObservableObject
         Recompute();
     }
 
+    [RelayCommand]
+    private async Task ShowPerformanceOverview()
+    {
+        if (SelectedRow is null || OnShowPerformanceOverview is null) return;
+        await OnShowPerformanceOverview(SelectedRow);
+        Recompute();
+    }
+
     [RelayCommand]
     private async Task CollectiveGrade()
     {
diff --git a/LehrerApp.Desktop/ViewModels/Groups/ParticipationViewModels.cs b/LehrerApp.Desktop/ViewModels/Groups/ParticipationViewModels.cs
index 8f01c2c..c3eacf0 100644
--- a/LehrerApp.Desktop/ViewModels/Groups/ParticipationViewModels.cs
+++ b/LehrerApp.Desktop/ViewModels/Groups/ParticipationViewModels.cs
@@ -158,6 +158,7 @@ public partial class ParticipationTabViewModel : ObservableObject
             row.OnCompetencyRatingChanged = (sid, code, val) => SaveCompetencyRating(sessionId, sid, code, val);
             row.HomeworkChangedCallback         = (sid, val) => SaveHomework(sessionId, sid, val);
             row.AttendanceChangedCallback       = (sid, val) => SaveAttendance(sessionId, sid, val);
+            row.DayHighlightChangedCallback     = (sid, val) => SaveDayHighlight(sessionId, sid, val);
             StudentRows.Add(row);
         }
         QuickInputCommand.NotifyCanExecuteChanged();
@@ -212,6 +213,15 @@ public partial class ParticipationTabViewModel : ObservableObject
         _entries.Save(entry);
     }
 
+    private void SaveDayHighlight(Guid sessionId, Guid studentId, DayHighlightKind? value)
+    {
+        if (IsReadOnly) return;
+        var entry = _entries.GetBySessionAndStudent(sessionId, studentId)
+                    ?? new ParticipationEntry { SessionId = sessionId, StudentId = studentId };
+        entry.DayHighlight = value;
+        _entries.Save(entry);
+    }
+
     [RelayCommand]
     private void ToggleCompetencyTags() => CompetencyTagsVisible = !CompetencyTagsVisible;
 
@@ -389,6 +399,7 @@ public partial class ParticipationStudentRow : ObservableObject
 
     [ObservableProperty] private HomeworkStatus? _homework;
     [ObservableProperty] private AttendanceStatus? _attendance;
+    [ObservableProperty] private DayHighlightKind? _dayHighlight;
 
     public string AttendanceLabel => AttendanceDisplay.ShortLabel(Attendance);
     public string AttendanceTooltip => AttendanceDisplay.Label(Attendance);
@@ -405,6 +416,7 @@ public partial class ParticipationStudentRow : ObservableObject
     public Action<Guid, string, int?>? OnCompetencyRatingChanged { get; set; }
     public Action<Guid, HomeworkStatus?>?  HomeworkChangedCallback   { get; set; }
     public Action<Guid, AttendanceStatus?>? AttendanceChangedCallback { get; set; }
+    public Action<Guid, DayHighlightKind?>? DayHighlightChangedCallback { get; set; }
 
     public ParticipationStudentRow(Guid id, string name, ParticipationEntry entry,
         List<AspectColumnDef> aspects, List<string> competencyCodes)
@@ -414,6 +426,7 @@ public partial class ParticipationStudentRow : ObservableObject
         _aspectDefs = aspects;
         _homework = HomeworkDisplay.Effective(entry);
         _attendance       = entry.Attendance;
+        _dayHighlight     = entry.DayHighlight;
 
         foreach (var a in aspects)
         {
@@ -463,6 +476,12 @@ public partial class ParticipationStudentRow : ObservableObject
         HomeworkChangedCallback?.Invoke(StudentId, value);
     }
 
+    public void SetDayHighlight(DayHighlightKind? value)
+    {
+        DayHighlight = value;
+        DayHighlightChangedCallback?.Invoke(StudentId, value);
+    }
+
     [RelayCommand]
     private void CycleAttendance()
     {
@@ -614,6 +633,27 @@ public static class AttendanceDisplay
     };
 }
 
+// ── Tagesflagge (Nutzer-Feedback) ──────────────────────────────────────────────
+
+public static class DayHighlightDisplay
+{
+    public static string Symbol(DayHighlightKind? kind) => kind switch
+    {
+        DayHighlightKind.Standout => "👑",
+        DayHighlightKind.Sleepy   => "😴",
+        DayHighlightKind.Rough    => "⚡",
+        _                         => "",
+    };
+
+    public static string Label(DayHighlightKind? kind) => kind switch
+    {
+        DayHighlightKind.Standout => "Spitzentag",
+        DayHighlightKind.Sleepy   => "Schlaftag",
+        DayHighlightKind.Rough    => "Schlechter Tag",
+        _                         => "Keine Markierung",
+    };
+}
+
 // ── Eine Bewertungszelle ──────────────────────────────────────────────────────
 
 public partial class RatingCell : ObservableObject
@@ -800,12 +840,31 @@ public partial class QuickInputViewModel : ObservableObject
     [ObservableProperty] private string _progressText = "";
     [ObservableProperty] private bool   _currentStudentIsAbsent;
     [ObservableProperty] private string _currentStudentAttendanceLabel = "";
+    [ObservableProperty] private DayHighlightKind? _currentStudentDayHighlight;
 
     /// Dimmt Name/Aspektliste, wenn der aktuelle Schüler abwesend ist — kein Blockieren der
     /// Eingabe (manche Bewertungssysteme wollen trotzdem einen Eintrag, z.B. "0 Punkte"), nur ein
     /// visueller Hinweis, dass eine Bewertung hier normalerweise keinen Sinn ergibt.
     public double CurrentStudentContentOpacity => CurrentStudentIsAbsent ? 0.4 : 1.0;
 
+    /// Tagesflagge (Nutzer-Feedback): Fallback für Kurse ohne Sitzplan — im Sitzplatz-Dialog gibt
+    /// es dieselbe Auswahl bereits über SeatAssessmentViewModel.DayHighlightChoices.
+    public string CurrentStudentDayHighlightSymbol => DayHighlightDisplay.Symbol(CurrentStudentDayHighlight);
+    public string CurrentStudentDayHighlightLabel => DayHighlightDisplay.Label(CurrentStudentDayHighlight);
+
+    public void SetDayHighlight(DayHighlightKind? value)
+    {
+        if (_rows.Count == 0) return;
+        _rows[StudentIndex].SetDayHighlight(value);
+        CurrentStudentDayHighlight = value;
+    }
+
+    partial void OnCurrentStudentDayHighlightChanged(DayHighlightKind? value)
+    {
+        OnPropertyChanged(nameof(CurrentStudentDayHighlightSymbol));
+        OnPropertyChanged(nameof(CurrentStudentDayHighlightLabel));
+    }
+
     public ObservableCollection<QuickAspectRow> AspectRows { get; } = [];
 
     /// Wechselt je nach Typ des aktuell gewählten Aspekts (3.1.3) — Scale3/Binary haben andere
@@ -824,7 +883,8 @@ public partial class QuickInputViewModel : ObservableObject
                 _ => "1–5 bewerten",
             };
             return $"{ratingHint}  ·  Q/W/E/R/T Aspekt wählen  ·  Leertaste/↓ nächster Aspekt  ·  ↑ vorheriger Aspekt  ·  " +
-                   "Enter/→ nächster Schüler  ·  Backspace/← vorheriger Schüler  ·  +/− anpassen  ·  Entf nicht bewertet  ·  Esc schließen";
+                   "Enter/→ nächster Schüler  ·  Backspace/← vorheriger Schüler  ·  +/− anpassen  ·  Entf nicht bewertet  ·  " +
+                   "⇧1/2/3 Tagesflagge, ⇧0 löschen  ·  Esc schließen";
         }
     }
 
@@ -852,6 +912,7 @@ public partial class QuickInputViewModel : ObservableObject
         ProgressText = $"{index + 1} / {_rows.Count}";
         CurrentStudentIsAbsent = row.IsAbsent;
         CurrentStudentAttendanceLabel = row.AttendanceTooltip;
+        CurrentStudentDayHighlight = row.DayHighlight;
 
         AspectRows.Clear();
         foreach (var (a, i) in _aspects.Select((a, i) => (a, i)))
diff --git a/LehrerApp.Desktop/ViewModels/Groups/SeatingPlanViewModels.cs b/LehrerApp.Desktop/ViewModels/Groups/SeatingPlanViewModels.cs
index 7d21db3..e89ccc3 100644
--- a/LehrerApp.Desktop/ViewModels/Groups/SeatingPlanViewModels.cs
+++ b/LehrerApp.Desktop/ViewModels/Groups/SeatingPlanViewModels.cs
@@ -547,11 +547,13 @@ public partial class SeatCellViewModel : ObservableObject
     [ObservableProperty] private double _lessonOpacity = 1.0;
     [ObservableProperty] private string _attendanceBadge = "";
     [ObservableProperty] private string _homeworkBadge = "";
+    [ObservableProperty] private string _dayHighlightBadge = "";
     [ObservableProperty] private int _raisedHandCount;
     [ObservableProperty] private int _calledOnCount;
     public ObservableCollection<SituationTagChoice> SituationTags { get; } = [];
     public bool HasAttendanceBadge => AttendanceBadge.Length > 0;
     public bool HasHomeworkBadge => HomeworkBadge.Length > 0;
+    public bool HasDayHighlightBadge => DayHighlightBadge.Length > 0;
     public bool ShowLessonOverview => IsOccupied && !CanEdit;
     [ObservableProperty] private bool _canRecordLesson;
     public bool IsOccupied => SelectedOption.StudentId.HasValue;
@@ -644,6 +646,7 @@ public partial class SeatCellViewModel : ObservableObject
         var attendance = entry?.Attendance;
         AttendanceBadge = attendance is null ? "" : AttendanceDisplay.ShortLabel(attendance);
         HomeworkBadge = entry is null ? "" : HomeworkDisplay.Symbol(HomeworkDisplay.Effective(entry));
+        DayHighlightBadge = DayHighlightDisplay.Symbol(entry?.DayHighlight);
         RaisedHandCount = entry?.RaisedHandCount ?? 0;
         CalledOnCount = entry?.CalledOnCount ?? 0;
         LessonOpacity = attendance is not null and not AttendanceStatus.Present
@@ -652,6 +655,7 @@ public partial class SeatCellViewModel : ObservableObject
         foreach (var choice in SituationTags) choice.IsSelected = selected.Contains(choice.Text);
         OnPropertyChanged(nameof(HasAttendanceBadge));
         OnPropertyChanged(nameof(HasHomeworkBadge));
+        OnPropertyChanged(nameof(HasDayHighlightBadge));
     }
 }
 
@@ -677,6 +681,7 @@ public partial class SeatAssessmentViewModel : ObservableObject
     [ObservableProperty] private int _selectedAspectIndex;
     [ObservableProperty] private string _attendanceLabel = "Noch nicht kontrolliert";
     [ObservableProperty] private string _homeworkLabel = "Keine Hausaufgabe aufgegeben";
+    [ObservableProperty] private string _dayHighlightLabel = "Keine Markierung";
 
     public string StudentName { get; }
     public string SessionDisplay { get; }
@@ -687,6 +692,7 @@ public partial class SeatAssessmentViewModel : ObservableObject
     public ObservableCollection<SeatAssessmentAspectRow> AspectRows { get; } = [];
     public ObservableCollection<SeatAttendanceChoice> AttendanceChoices { get; } = [];
     public ObservableCollection<SeatHomeworkChoice> HomeworkChoices { get; } = [];
+    public ObservableCollection<SeatDayHighlightChoice> DayHighlightChoices { get; } = [];
 
     public SeatAssessmentViewModel(IParticipationSessionRepository sessions,
         IParticipationRepository entries, IParticipationAspectRepository aspects,
@@ -729,6 +735,7 @@ public partial class SeatAssessmentViewModel : ObservableObject
 
         BuildAttendanceChoices();
         BuildHomeworkChoices();
+        BuildDayHighlightChoices();
         RefreshStatusChoices();
         SelectAspect(0);
     }
@@ -761,6 +768,17 @@ public partial class SeatAssessmentViewModel : ObservableObject
         HomeworkChoices.Add(new("·", "Keine aufgegeben", "⌥X", null, SetHomework));
     }
 
+    private void BuildDayHighlightChoices()
+    {
+        DayHighlightChoices.Add(new(DayHighlightDisplay.Symbol(DayHighlightKind.Standout),
+            DayHighlightDisplay.Label(DayHighlightKind.Standout), "⇧1", DayHighlightKind.Standout, SetDayHighlight));
+        DayHighlightChoices.Add(new(DayHighlightDisplay.Symbol(DayHighlightKind.Sleepy),
+            DayHighlightDisplay.Label(DayHighlightKind.Sleepy), "⇧2", DayHighlightKind.Sleepy, SetDayHighlight));
+        DayHighlightChoices.Add(new(DayHighlightDisplay.Symbol(DayHighlightKind.Rough),
+            DayHighlightDisplay.Label(DayHighlightKind.Rough), "⇧3", DayHighlightKind.Rough, SetDayHighlight));
+        DayHighlightChoices.Add(new("·", "Keine Markierung", "⇧X", null, SetDayHighlight));
+    }
+
     public void SelectAspect(int index)
     {
         if (index < 0 || index >= AspectRows.Count) return;
@@ -827,6 +845,17 @@ public partial class SeatAssessmentViewModel : ObservableObject
         if (clear || digit is 0 or 1 or 3 or 4 or 5 or 7 or 8) SetHomework(status);
     }
 
+    public void ApplyDayHighlightShortcut(int? digit, bool clear)
+    {
+        if (!CanEdit) return;
+        var kind = clear ? null : digit switch
+        {
+            1 => DayHighlightKind.Standout, 2 => DayHighlightKind.Sleepy, 3 => DayHighlightKind.Rough,
+            _ => (DayHighlightKind?)null,
+        };
+        if (clear || digit is 1 or 2 or 3) SetDayHighlight(kind);
+    }
+
     private void ApplyRating(string key, int? value)
     {
         if (!CanEdit || _entry is null) return;
@@ -857,13 +886,23 @@ public partial class SeatAssessmentViewModel : ObservableObject
         RefreshStatusChoices();
     }
 
+    private void SetDayHighlight(DayHighlightKind? kind)
+    {
+        if (!CanEdit || _entry is null) return;
+        _entry.DayHighlight = kind;
+        _entries.Save(_entry);
+        RefreshStatusChoices();
+    }
+
     private void RefreshStatusChoices()
     {
         AttendanceLabel = AttendanceDisplay.Label(_entry?.Attendance);
         HomeworkLabel = HomeworkDisplay.Label(_entry is null ? null : HomeworkDisplay.Effective(_entry));
+        DayHighlightLabel = DayHighlightDisplay.Label(_entry?.DayHighlight);
         foreach (var choice in AttendanceChoices) choice.IsSelected = choice.Status == _entry?.Attendance;
         var homework = _entry is null ? null : HomeworkDisplay.Effective(_entry);
         foreach (var choice in HomeworkChoices) choice.IsSelected = choice.Status == homework;
+        foreach (var choice in DayHighlightChoices) choice.IsSelected = choice.Kind == _entry?.DayHighlight;
     }
 }
 
@@ -966,6 +1005,17 @@ public partial class SeatHomeworkChoice(string symbol, string label, string shor
     [RelayCommand] private void Apply() => apply(Status);
 }
 
+public partial class SeatDayHighlightChoice(string symbol, string label, string shortcut,
+    DayHighlightKind? kind, Action<DayHighlightKind?> apply) : ObservableObject
+{
+    public string Symbol { get; } = symbol;
+    public string Label { get; } = label;
+    public string Shortcut { get; } = shortcut;
+    public DayHighlightKind? Kind { get; } = kind;
+    [ObservableProperty] private bool _isSelected;
+    [RelayCommand] private void Apply() => apply(Kind);
+}
+
 public partial class SeatingPlanDialogViewModel : ObservableObject
 {
     private readonly ISeatingPlanRepository _plans;
diff --git a/LehrerApp.Desktop/ViewModels/Groups/StudentPerformanceOverviewViewModel.cs b/LehrerApp.Desktop/ViewModels/Groups/StudentPerformanceOverviewViewModel.cs
new file mode 100644
index 0000000..907a9a1
--- /dev/null
+++ b/LehrerApp.Desktop/ViewModels/Groups/StudentPerformanceOverviewViewModel.cs
@@ -0,0 +1,310 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+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;
+using System.Globalization;
+
+namespace LehrerApp.Desktop.ViewModels.Groups;
+
+// ── Schüler-Leistungsüberblick + Zielnoten-Rechner (Nutzer-Feedback) ─────────────
+//
+// Zeigt die Leistungen eines einzelnen Schülers in einem Kurs im Überblick — Klausuren,
+// Mitarbeit- und sonstige Noten, die daraus berechnete Zeugnisnote sowie zwei Rechner
+// ("Zielnote": was brauche ich noch? / "Was-wäre-wenn": wie wirkt sich eine zusätzliche
+// Klausurnote aus?). Bewusst pro Kurs statt fächerübergreifend, da Gewichtungsschema und
+// Notensystem am Kurs hängen. Zwei Modi über IsTeacherMode: im Bewertermodus zusätzlich
+// Kursdurchschnitt je Klausur und Bearbeitbarkeit der Mitarbeit-/Sonstige-Noten; im
+// Schülermodus ausschließlich die eigenen Werte, rein lesend — gedacht, um den Bildschirm im
+// Gespräch umzudrehen. Exam-Noten bleiben bewusst nur lesbar: eine Korrektur läuft weiterhin
+// über den bestehenden ExamGradingDialog, der die Punkte-Struktur konsistent hält — direktes
+// Überschreiben von Exam.Grade hier könnte mit ExamResult.Points/TotalPoints auseinanderlaufen.
+public partial class StudentPerformanceOverviewViewModel : ObservableObject
+{
+    private readonly IGradeRepository _grades;
+    private readonly IExamRepository _exams;
+    private readonly IExamResultRepository _results;
+    private readonly IGroupMembershipRepository _memberships;
+    private readonly IGradingSchemeRepository _schemes;
+    private readonly GradingService _grading;
+
+    private readonly Guid _groupId;
+    private readonly Guid _studentId;
+    private readonly GroupType _groupType;
+    private readonly GradingSystem _gradingSystem;
+    private readonly string _schoolYear;
+
+    private GradingScheme _scheme = new();
+    private double? _examsAverage;
+    private double? _participationAverage;
+    private double? _otherAverage;
+    private List<(string Grade, double Weight)> _examGradesRaw = [];
+    private List<(string Grade, double Weight)> _participationGradesRaw = [];
+    private List<(string Grade, double Weight)> _otherGradesRaw = [];
+
+    public string StudentName { get; }
+    public string GroupLabel { get; }
+
+    [ObservableProperty] private ParticipationPeriodOption _selectedPeriod;
+    [ObservableProperty] private bool _isTeacherMode = true;
+    [ObservableProperty] private string _schemeSummary = "";
+    [ObservableProperty] private string? _examsAverageDisplay;
+    [ObservableProperty] private string? _participationAverageDisplay;
+    [ObservableProperty] private string? _otherAverageDisplay;
+    [ObservableProperty] private string _currentReportGradeDisplay = "";
+
+    [ObservableProperty] private string _targetGradeText = "";
+    [ObservableProperty] private GradeBucketKind _targetBucket = GradeBucketKind.Exams;
+    [ObservableProperty] private string _targetResultDisplay = "";
+
+    [ObservableProperty] private string _whatIfExamGradeText = "";
+    [ObservableProperty] private string _whatIfResultDisplay = "";
+
+    public List<ParticipationPeriodOption> PeriodOptions { get; } =
+    [
+        new(ParticipationPeriod.FullYear, "Gesamtes Schuljahr"),
+        new(ParticipationPeriod.H1, "1. Halbjahr"),
+        new(ParticipationPeriod.H2, "2. Halbjahr"),
+    ];
+
+    public string[] TargetBucketOptions { get; } = ["Klausuren", "Mitarbeit", "Sonstige"];
+
+    public string TargetBucketName
+    {
+        get => TargetBucket switch
+        {
+            GradeBucketKind.Participation => "Mitarbeit",
+            GradeBucketKind.Other => "Sonstige",
+            _ => "Klausuren",
+        };
+        set => TargetBucket = value switch
+        {
+            "Mitarbeit" => GradeBucketKind.Participation,
+            "Sonstige" => GradeBucketKind.Other,
+            _ => GradeBucketKind.Exams,
+        };
+    }
+
+    public ObservableCollection<StudentExamRow> ExamRows { get; } = [];
+    /// Eigener Verlauf (Nutzer-Feedback): dieselbe Balken-Sparkline wie die bestehende
+    /// Notenentwicklung im Schülerdetail (2.5), hier nur auf die Klausuren dieses Kurses
+    /// beschränkt statt aller Lerngruppen — passt zum Kursdurchschnitt-Vergleich je Klausur.
+    public StudentGradeHistoryGroup ExamHistory { get; } = new("Klausurverlauf");
+    public ObservableCollection<StudentSimpleGradeRow> ParticipationRows { get; } = [];
+    public ObservableCollection<StudentSimpleGradeRow> OtherRows { get; } = [];
+
+    public StudentPerformanceOverviewViewModel(IGradeRepository grades, IExamRepository exams,
+        IExamResultRepository results, IGroupMembershipRepository memberships,
+        IGradingSchemeRepository schemes, GradingService grading,
+        Guid groupId, Guid studentId, GroupType groupType, GradingSystem gradingSystem,
+        string studentName, string groupLabel, string schoolYear)
+    {
+        _grades = grades; _exams = exams; _results = results; _memberships = memberships;
+        _schemes = schemes; _grading = grading;
+        _groupId = groupId; _studentId = studentId; _groupType = groupType;
+        _gradingSystem = gradingSystem; _schoolYear = schoolYear;
+        StudentName = studentName; GroupLabel = groupLabel;
+
+        _selectedPeriod = PeriodOptions[0];
+        Recompute();
+    }
+
+    partial void OnSelectedPeriodChanged(ParticipationPeriodOption value) => Recompute();
+
+    public string ModeButtonLabel => IsTeacherMode ? "Modus: Bewerter" : "Modus: Schüler";
+
+    partial void OnIsTeacherModeChanged(bool value) => OnPropertyChanged(nameof(ModeButtonLabel));
+
+    [RelayCommand]
+    private void ToggleMode() => IsTeacherMode = !IsTeacherMode;
+
+    private GradingScheme ResolveScheme() =>
+        _schemes.GetByGroup(_groupId)
+        ?? _schemes.GetDefaultForType(_groupType)
+        ?? new GradingScheme { ExamsPercent = 50, ParticipationPercent = 40, OtherPercent = 10 };
+
+    private void Recompute()
+    {
+        _scheme = ResolveScheme();
+        SchemeSummary = $"Klausuren {_scheme.ExamsPercent:0.#} % · Mitarbeit {_scheme.ParticipationPercent:0.#} % · " +
+                         $"Sonstige {_scheme.OtherPercent:0.#} %";
+
+        var (periodFrom, periodTo) = GroupMembershipService.SchoolYearPeriod(_schoolYear, SelectedPeriod.Period switch
+        {
+            ParticipationPeriod.H1 => SchoolYearPeriodKind.H1,
+            ParticipationPeriod.H2 => SchoolYearPeriodKind.H2,
+            _ => SchoolYearPeriodKind.FullYear,
+        });
+        var membership = _memberships.GetByGroup(_groupId).FirstOrDefault(m => m.StudentId == _studentId);
+
+        // ── Klausuren ─────────────────────────────────────────────────────
+        ExamRows.Clear();
+        ExamHistory.Points.Clear();
+        _examGradesRaw = [];
+        int? previousNoteEquivalent = null;
+        foreach (var exam in _exams.GetByGroup(_groupId)
+                     .Where(e => e.Date >= periodFrom && e.Date <= periodTo)
+                     .Where(e => membership is null || GroupMembershipService.IsActiveOn(membership, e.Date))
+                     .Where(e => !e.Niveau.HasValue || membership?.Niveau == e.Niveau)
+                     .OrderBy(e => e.Date))
+        {
+            var allResults = _results.GetByExam(exam.Id);
+            var own = allResults.FirstOrDefault(r => r.StudentId == _studentId);
+            string? ownGrade = own is { Absent: false, Grade: not null } ? own.Grade : null;
+            if (ownGrade is not null) _examGradesRaw.Add((ownGrade, 1.0));
+
+            var classGrades = allResults.Where(r => !r.Absent && r.Grade is not null)
+                .Select(r => (r.Grade!, 1.0)).ToList();
+            var classAverage = classGrades.Count > 0 ? _grading.WeightedAverage(classGrades) : (double?)null;
+
+            ExamRows.Add(new StudentExamRow(exam.Title, exam.Date, ownGrade,
+                classAverage.HasValue ? FormatGrade(classAverage.Value) : "–"));
+
+            // Gleiche Balken-Sparkline wie die bestehende Notenentwicklung (2.5): Rohwert auf die
+            // 1..6-Notenäquivalent-Achse abbilden, damit Grades1To6 und Points0To15 dieselbe
+            // Balkenhöhen-Formel nutzen können.
+            int? noteEquivalent = ownGrade is not null && int.TryParse(ownGrade, out var raw)
+                ? (_gradingSystem == GradingSystem.Grades1To6 ? raw : int.Parse(PointsNoteMapping.PointsToNote(raw)))
+                : null;
+            var isFailing = noteEquivalent is >= 5;
+            var isDrop = noteEquivalent.HasValue && previousNoteEquivalent.HasValue
+                         && noteEquivalent.Value - previousNoteEquivalent.Value >= 1;
+            var warnings = new List<string>();
+            if (isDrop) warnings.Add("Abfall um ≥ 1 Note");
+            if (isFailing) warnings.Add("Versetzungsgefährdung");
+            ExamHistory.Points.Add(new GradeHistoryPoint(exam.Date, exam.Title, ownGrade ?? "–",
+                noteEquivalent, warnings.Count > 0, string.Join(" · ", warnings)));
+            if (noteEquivalent.HasValue) previousNoteEquivalent = noteEquivalent;
+        }
+        _examsAverage = _examGradesRaw.Count > 0 ? _grading.WeightedAverage(_examGradesRaw) : null;
+
+        // ── Mitarbeit & Sonstige ──────────────────────────────────────────
+        var allGrades = _grades.GetByStudentAndGroup(_studentId, _groupId)
+            .Where(g => g.Date >= periodFrom && g.Date <= periodTo)
+            .Where(g => membership is null || GroupMembershipService.IsActiveOn(membership, g.Date))
+            .OrderBy(g => g.Date).ToList();
+
+        ParticipationRows.Clear();
+        _participationGradesRaw = [];
+        foreach (var g in allGrades.Where(g => g.Category == GradeCategory.Participation))
+        {
+            _participationGradesRaw.Add((g.Value, g.Weight));
+            ParticipationRows.Add(new StudentSimpleGradeRow(g, SaveGrade));
+        }
+        _participationAverage = _participationGradesRaw.Count > 0 ? _grading.WeightedAverage(_participationGradesRaw) : null;
+
+        OtherRows.Clear();
+        _otherGradesRaw = [];
+        foreach (var g in allGrades.Where(g => g.Category != GradeCategory.Participation))
+        {
+            _otherGradesRaw.Add((g.Value, g.Weight));
+            OtherRows.Add(new StudentSimpleGradeRow(g, SaveGrade));
+        }
+        _otherAverage = _otherGradesRaw.Count > 0 ? _grading.WeightedAverage(_otherGradesRaw) : null;
+
+        ExamsAverageDisplay = _examsAverage.HasValue ? FormatGrade(_examsAverage.Value) : null;
+        ParticipationAverageDisplay = _participationAverage.HasValue ? FormatGrade(_participationAverage.Value) : null;
+        OtherAverageDisplay = _otherAverage.HasValue ? FormatGrade(_otherAverage.Value) : null;
+
+        var reportGrade = _grading.CalculateReportGrade(_examGradesRaw, _participationGradesRaw, _otherGradesRaw,
+            _scheme, _gradingSystem, RoundingRule.Commercial);
+        CurrentReportGradeDisplay = reportGrade is null
+            ? "Noch nicht berechenbar — keine Werte im gewählten Zeitraum."
+            : $"Note {reportGrade}";
+
+        RecomputeTarget();
+        RecomputeWhatIf();
+    }
+
+    private void SaveGrade(Grade grade)
+    {
+        _grades.Save(grade);
+        Recompute();
+    }
+
+    partial void OnTargetGradeTextChanged(string value) => RecomputeTarget();
+    partial void OnTargetBucketChanged(GradeBucketKind value)
+    {
+        OnPropertyChanged(nameof(TargetBucketName));
+        RecomputeTarget();
+    }
+
+    private void RecomputeTarget()
+    {
+        if (!TryParseGrade(TargetGradeText, out var target))
+        {
+            TargetResultDisplay = "";
+            return;
+        }
+
+        var result = ReportGradeTargetCalculator.SolveRequiredAverage(target, TargetBucket,
+            _examsAverage, _participationAverage, _otherAverage, _scheme, _gradingSystem);
+
+        TargetResultDisplay = result switch
+        {
+            null => $"{TargetBucketName} fließt laut Gewichtungsschema nicht in die Zeugnisnote ein.",
+            { IsAchievable: true } r => $"Nötiger Schnitt in {TargetBucketName}: {FormatGrade(r.RequiredAverage)}",
+            { IsAchievable: false } r =>
+                $"Mit den übrigen Bereichen rechnerisch nicht mehr erreichbar (bräuchte {FormatGrade(r.RequiredAverage)}).",
+        };
+    }
+
+    partial void OnWhatIfExamGradeTextChanged(string value) => RecomputeWhatIf();
+
+    private void RecomputeWhatIf()
+    {
+        if (string.IsNullOrWhiteSpace(WhatIfExamGradeText))
+        {
+            WhatIfResultDisplay = "";
+            return;
+        }
+
+        var hypothetical = new List<(string Grade, double Weight)>(_examGradesRaw) { (WhatIfExamGradeText.Trim(), 1.0) };
+        var result = _grading.CalculateReportGrade(hypothetical, _participationGradesRaw, _otherGradesRaw,
+            _scheme, _gradingSystem, RoundingRule.Commercial);
+        WhatIfResultDisplay = result is null
+            ? "Ungültige Note."
+            : $"Zeugnisnote mit dieser zusätzlichen Klausurnote: {result}";
+    }
+
+    private static bool TryParseGrade(string text, out double value) =>
+        double.TryParse(text.Trim().Replace(',', '.'), NumberStyles.Float, CultureInfo.InvariantCulture, out value);
+
+    private static string FormatGrade(double value) => value.ToString("0.0", CultureInfo.InvariantCulture);
+}
+
+public class StudentExamRow(string title, DateOnly date, string? ownGrade, string classAverageDisplay)
+{
+    public string Title { get; } = title;
+    public string DateDisplay { get; } = date.ToString("dd.MM.yyyy");
+    public string OwnGradeDisplay { get; } = ownGrade ?? "–";
+    public string ClassAverageDisplay { get; } = classAverageDisplay;
+}
+
+public partial class StudentSimpleGradeRow : ObservableObject
+{
+    private readonly Grade _grade;
+    private readonly Action<Grade> _save;
+
+    public string CategoryLabel { get; }
+    public string DateDisplay { get; }
+    [ObservableProperty] private string _value;
+
+    public StudentSimpleGradeRow(Grade grade, Action<Grade> save)
+    {
+        _grade = grade;
+        _save = save;
+        CategoryLabel = GradeCategoryDisplay.Label(grade.Category);
+        DateDisplay = grade.Date.ToString("dd.MM.yyyy");
+        _value = grade.Value;
+    }
+
+    [RelayCommand]
+    private void Save()
+    {
+        _grade.Value = Value.Trim();
+        _save(_grade);
+    }
+}
diff --git a/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml b/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml
index 1541205..2366e7a 100644
--- a/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml
+++ b/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml
@@ -19,6 +19,9 @@
       <Button Content="Noten verwalten" Command="{Binding ManageStudentGradesCommand}" Margin="12,0,0,0"
               IsVisible="{Binding SelectedRow, Converter={x:Static ObjectConverters.IsNotNull}}"
               IsEnabled="{Binding !IsReadOnly}"/>
+      <Button Content="Überblick" Command="{Binding ShowPerformanceOverviewCommand}" Margin="6,0,0,0"
+              IsVisible="{Binding SelectedRow, Converter={x:Static ObjectConverters.IsNotNull}}"
+              ToolTip.Tip="Leistungsüberblick mit Zielnoten-Rechner für diesen Schüler"/>
       <Button Content="＋ Sammelnote" Command="{Binding CollectiveGradeCommand}" IsEnabled="{Binding !IsReadOnly}"/>
       <Button Content="Zeugnisnoten" Command="{Binding ReportGradesCommand}" IsEnabled="{Binding !IsReadOnly}"/>
       <Button Content="Als PDF" Click="OnExportPdfClick" Margin="12,0,0,0"
diff --git a/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml.cs b/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml.cs
index bae231a..ef41c96 100644
--- a/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml.cs
+++ b/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml.cs
@@ -25,6 +25,7 @@ public partial class GradeOverviewTabView : UserControl
             vm.OnManageStudentGrades = ShowStudentGradesDialog;
             vm.OnCollectiveGrade = ShowCollectiveGradeDialog;
             vm.OnReportGrades = ShowReportGradesDialog;
+            vm.OnShowPerformanceOverview = ShowPerformanceOverviewDialog;
             vm.PropertyChanged += (_, pe) =>
             {
                 if (pe.PropertyName == nameof(GradeOverviewTabViewModel.RebuildColumnsSignal))
@@ -79,6 +80,22 @@ public partial class GradeOverviewTabView : UserControl
         if (owner is not null) await dialog.ShowDialog(owner);
     }
 
+    private async Task ShowPerformanceOverviewDialog(GradeOverviewRow row)
+    {
+        var dialogVm = new StudentPerformanceOverviewViewModel(
+            App.Services.GetRequiredService<IGradeRepository>(),
+            App.Services.GetRequiredService<IExamRepository>(),
+            App.Services.GetRequiredService<IExamResultRepository>(),
+            App.Services.GetRequiredService<IGroupMembershipRepository>(),
+            App.Services.GetRequiredService<IGradingSchemeRepository>(),
+            App.Services.GetRequiredService<GradingService>(),
+            _vm!.GroupId, row.StudentId, _vm.GroupType, _vm.GradingSystem, row.Name, _vm.GroupLabel, _vm.SchoolYear);
+
+        var dialog = new StudentPerformanceOverviewDialog { DataContext = dialogVm };
+        var owner = TopLevel.GetTopLevel(this) as Window;
+        if (owner is not null) await dialog.ShowDialog(owner);
+    }
+
     private async void OnExportPdfClick(object? sender, RoutedEventArgs e)
     {
         var topLevel = TopLevel.GetTopLevel(this);
diff --git a/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml b/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml
index 345d674..719522a 100644
--- a/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml
+++ b/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml
@@ -12,8 +12,12 @@
     <!-- Schülername + Fortschritt -->
     <Grid Grid.Row="0" ColumnDefinitions="*,Auto" Margin="0,0,0,16">
       <StackPanel Grid.Column="0">
-        <TextBlock Text="{Binding StudentName}" FontSize="22" FontWeight="SemiBold"
-                   Opacity="{Binding CurrentStudentContentOpacity}"/>
+        <StackPanel Orientation="Horizontal" Spacing="6">
+          <TextBlock Text="{Binding StudentName}" FontSize="22" FontWeight="SemiBold"
+                     Opacity="{Binding CurrentStudentContentOpacity}"/>
+          <TextBlock Text="{Binding CurrentStudentDayHighlightSymbol}" FontSize="20"
+                     VerticalAlignment="Center" ToolTip.Tip="{Binding CurrentStudentDayHighlightLabel}"/>
+        </StackPanel>
         <TextBlock Text="{Binding CurrentAspectLabel}" FontSize="13" Opacity="0.5"
                    IsVisible="{Binding !CurrentStudentIsAbsent}"/>
         <TextBlock Text="{Binding CurrentStudentAttendanceLabel, StringFormat='⚠ Abwesend — {0}'}"
diff --git a/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml.cs b/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml.cs
index cfea0a5..7048ea7 100644
--- a/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml.cs
+++ b/LehrerApp.Desktop/Views/Groups/ParticipationQuickInputDialog.axaml.cs
@@ -1,6 +1,7 @@
 using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Interactivity;
+using LehrerApp.Core.Models;
 using LehrerApp.Desktop.ViewModels.Groups;
 
 namespace LehrerApp.Desktop.Views.Groups;
@@ -19,6 +20,18 @@ public partial class ParticipationQuickInputDialog : Window
     {
         if (DataContext is not QuickInputViewModel vm) { base.OnKeyDown(e); return; }
 
+        if (e.KeyModifiers.HasFlag(KeyModifiers.Shift))
+        {
+            switch (e.Key)
+            {
+                case Key.D1 or Key.NumPad1: vm.SetDayHighlight(DayHighlightKind.Standout); e.Handled = true; break;
+                case Key.D2 or Key.NumPad2: vm.SetDayHighlight(DayHighlightKind.Sleepy);   e.Handled = true; break;
+                case Key.D3 or Key.NumPad3: vm.SetDayHighlight(DayHighlightKind.Rough);    e.Handled = true; break;
+                case Key.D0 or Key.NumPad0: vm.SetDayHighlight(null);                      e.Handled = true; break;
+            }
+            if (e.Handled) return;
+        }
+
         switch (e.Key)
         {
             case Key.D0 or Key.NumPad0: vm.SetRatingByNumber(0); e.Handled = true; break;
diff --git a/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml b/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml
index 2349690..d9e473f 100644
--- a/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml
+++ b/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml
@@ -128,10 +128,30 @@
             </ItemsControl.ItemTemplate>
           </ItemsControl>
         </StackPanel>
+
+        <StackPanel Spacing="7">
+          <TextBlock Text="TAGESFLAGGE" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+          <TextBlock Text="{Binding DayHighlightLabel}" FontSize="12"/>
+          <ItemsControl ItemsSource="{Binding DayHighlightChoices}">
+            <ItemsControl.ItemsPanel><ItemsPanelTemplate><WrapPanel/></ItemsPanelTemplate></ItemsControl.ItemsPanel>
+            <ItemsControl.ItemTemplate>
+              <DataTemplate x:DataType="vm:SeatDayHighlightChoice">
+                <Button Classes="choice" Classes.selected="{Binding IsSelected}"
+                        Command="{Binding ApplyCommand}" Margin="2">
+                  <StackPanel Orientation="Horizontal" Spacing="5">
+                    <TextBlock Text="{Binding Symbol}" FontWeight="Bold"/>
+                    <TextBlock Text="{Binding Label}"/>
+                    <TextBlock Text="{Binding Shortcut}" FontSize="9" Opacity="0.5" VerticalAlignment="Center"/>
+                  </StackPanel>
+                </Button>
+              </DataTemplate>
+            </ItemsControl.ItemTemplate>
+          </ItemsControl>
+        </StackPanel>
       </StackPanel>
     </ScrollViewer>
 
     <TextBlock Grid.Row="2" Margin="0,12,0,0" FontSize="10" Opacity="0.55" TextWrapping="Wrap"
-               Text="Mitarbeit: Q/W/E/R/T Aspekt · 1–5 Bewertung · +/− anpassen · Backspace löschen · ←/→ Aspekt  |  Anwesenheit: Strg+1/2/5/7/9/0, Strg+X  |  Hausaufgaben: ⌥+1/3/4/5/7/8/0, ⌥+X  |  Esc schließen"/>
+               Text="Mitarbeit: Q/W/E/R/T Aspekt · 1–5 Bewertung · +/− anpassen · Backspace löschen · ←/→ Aspekt  |  Anwesenheit: Strg+1/2/5/7/9/0, Strg+X  |  Hausaufgaben: ⌥+1/3/4/5/7/8/0, ⌥+X  |  Tagesflagge: ⇧1/2/3, ⇧X  |  Esc schließen"/>
   </Grid>
 </Window>
diff --git a/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml.cs b/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml.cs
index 74b0ba7..3218354 100644
--- a/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml.cs
+++ b/LehrerApp.Desktop/Views/Groups/SeatAssessmentDialog.axaml.cs
@@ -36,6 +36,12 @@ public partial class SeatAssessmentDialog : Window
             e.Handled = clear || digit is not null;
             return;
         }
+        if (e.KeyModifiers.HasFlag(KeyModifiers.Shift))
+        {
+            if (clear || digit is not null) vm.ApplyDayHighlightShortcut(digit, clear);
+            e.Handled = clear || digit is not null;
+            return;
+        }
         if (digit is not null)
         {
             vm.SetRatingByNumber(digit.Value);
diff --git a/LehrerApp.Desktop/Views/Groups/SeatingPlanTabView.axaml b/LehrerApp.Desktop/Views/Groups/SeatingPlanTabView.axaml
index af3db2f..c323265 100644
--- a/LehrerApp.Desktop/Views/Groups/SeatingPlanTabView.axaml
+++ b/LehrerApp.Desktop/Views/Groups/SeatingPlanTabView.axaml
@@ -154,6 +154,9 @@
                           <TextBlock Text="{Binding HomeworkBadge}" Foreground="White" FontSize="10"
                                      ToolTip.Tip="Hausaufgabe"/>
                         </Border>
+                        <TextBlock Text="{Binding DayHighlightBadge}" FontSize="14"
+                                   IsVisible="{Binding HasDayHighlightBadge}"
+                                   ToolTip.Tip="Tagesflagge"/>
                       </StackPanel>
                       <!-- Strichliste Meldungen (Nutzer-Feedback): schnelles Mitzählen ohne den
                            vollen Bewertungsdialog zu öffnen -->
diff --git a/LehrerApp.Desktop/Views/Groups/StudentPerformanceOverviewDialog.axaml b/LehrerApp.Desktop/Views/Groups/StudentPerformanceOverviewDialog.axaml
new file mode 100644
index 0000000..1ad3cf6
--- /dev/null
+++ b/LehrerApp.Desktop/Views/Groups/StudentPerformanceOverviewDialog.axaml
@@ -0,0 +1,184 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.Groups"
+        xmlns:students="clr-namespace:LehrerApp.Desktop.ViewModels.Students"
+        x:Class="LehrerApp.Desktop.Views.Groups.StudentPerformanceOverviewDialog"
+        x:DataType="vm:StudentPerformanceOverviewViewModel"
+        Title="Leistungsüberblick"
+        Width="920" Height="720" MinWidth="700" MinHeight="520"
+        CanResize="True" WindowStartupLocation="CenterOwner">
+
+  <Grid RowDefinitions="Auto,Auto,*,Auto" Margin="24">
+
+    <Grid Grid.Row="0" ColumnDefinitions="*,Auto">
+      <StackPanel Grid.Column="0" Spacing="2">
+        <TextBlock Text="{Binding StudentName}" Classes="dialogtitle"/>
+        <TextBlock Text="{Binding GroupLabel}" FontSize="12" Opacity="0.6"/>
+      </StackPanel>
+      <Button Grid.Column="1" Content="{Binding ModeButtonLabel}"
+              Command="{Binding ToggleModeCommand}" VerticalAlignment="Top"
+              ToolTip.Tip="Zwischen Bewerter- und Schülermodus umschalten"/>
+    </Grid>
+
+    <StackPanel Grid.Row="1" Orientation="Horizontal" Spacing="12" Margin="0,12,0,10">
+      <StackPanel Orientation="Horizontal" Spacing="6">
+        <TextBlock Text="Zeitraum:" VerticalAlignment="Center"/>
+        <ComboBox ItemsSource="{Binding PeriodOptions}" SelectedItem="{Binding SelectedPeriod}" MinWidth="170"/>
+      </StackPanel>
+      <TextBlock Text="{Binding SchemeSummary}" FontSize="12" Opacity="0.6" VerticalAlignment="Center"
+                 IsVisible="{Binding IsTeacherMode}"/>
+    </StackPanel>
+
+    <ScrollViewer Grid.Row="2">
+      <Grid ColumnDefinitions="*,300">
+        <StackPanel Grid.Column="0" Spacing="18" Margin="0,0,16,0">
+
+          <StackPanel Spacing="6">
+            <Grid ColumnDefinitions="*,Auto">
+              <TextBlock Grid.Column="0" Text="KLAUSUREN" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+              <TextBlock Grid.Column="1" Text="{Binding ExamsAverageDisplay, StringFormat='Ø {0}'}"
+                         FontSize="12" Opacity="0.7" IsVisible="{Binding ExamsAverageDisplay, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+            </Grid>
+            <ItemsControl ItemsSource="{Binding ExamRows}">
+              <ItemsControl.ItemTemplate>
+                <DataTemplate x:DataType="vm:StudentExamRow">
+                  <Grid ColumnDefinitions="Auto,*,80,80" Margin="0,4">
+                    <TextBlock Grid.Column="0" Text="{Binding DateDisplay}" FontSize="12" Opacity="0.6" Width="80"/>
+                    <TextBlock Grid.Column="1" Text="{Binding Title}" FontSize="13"/>
+                    <TextBlock Grid.Column="2" Text="{Binding OwnGradeDisplay}" FontWeight="SemiBold"
+                               HorizontalAlignment="Right"/>
+                    <TextBlock Grid.Column="3" Text="{Binding ClassAverageDisplay}" Opacity="0.55"
+                               HorizontalAlignment="Right"
+                               IsVisible="{Binding $parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"
+                               ToolTip.Tip="Kursdurchschnitt dieser Klausur"/>
+                  </Grid>
+                </DataTemplate>
+              </ItemsControl.ItemTemplate>
+            </ItemsControl>
+            <TextBlock Text="Keine Klausuren im gewählten Zeitraum." Classes="emptyhint"
+                       IsVisible="{Binding !ExamRows.Count}"/>
+
+            <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled"
+                          IsVisible="{Binding !!ExamHistory.Points.Count}">
+              <ItemsControl ItemsSource="{Binding ExamHistory.Points}">
+                <ItemsControl.ItemsPanel>
+                  <ItemsPanelTemplate><StackPanel Orientation="Horizontal" Spacing="10"/></ItemsPanelTemplate>
+                </ItemsControl.ItemsPanel>
+                <ItemsControl.ItemTemplate>
+                  <DataTemplate x:DataType="students:GradeHistoryPoint">
+                    <StackPanel Width="46" VerticalAlignment="Bottom" ToolTip.Tip="{Binding TooltipText}">
+                      <Border Classes="historybar" Height="{Binding BarHeight}" Width="16" CornerRadius="2"
+                              HorizontalAlignment="Center" VerticalAlignment="Bottom"
+                              Classes.warning="{Binding IsWarning}"/>
+                      <TextBlock Text="{Binding Value}" FontSize="11" FontWeight="SemiBold"
+                                 HorizontalAlignment="Center" Margin="0,3,0,0"/>
+                      <TextBlock Text="{Binding DateDisplay}" FontSize="9" Opacity="0.5"
+                                 HorizontalAlignment="Center"/>
+                    </StackPanel>
+                  </DataTemplate>
+                </ItemsControl.ItemTemplate>
+                <ItemsControl.Styles>
+                  <Style Selector="Border.historybar">
+                    <Setter Property="Background" Value="{DynamicResource SystemControlBackgroundAccentBrush}"/>
+                  </Style>
+                  <Style Selector="Border.historybar.warning">
+                    <Setter Property="Background" Value="#E53935"/>
+                  </Style>
+                </ItemsControl.Styles>
+              </ItemsControl>
+            </ScrollViewer>
+          </StackPanel>
+
+          <StackPanel Spacing="6">
+            <Grid ColumnDefinitions="*,Auto">
+              <TextBlock Grid.Column="0" Text="MITARBEIT" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+              <TextBlock Grid.Column="1" Text="{Binding ParticipationAverageDisplay, StringFormat='Ø {0}'}"
+                         FontSize="12" Opacity="0.7" IsVisible="{Binding ParticipationAverageDisplay, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+            </Grid>
+            <ItemsControl ItemsSource="{Binding ParticipationRows}">
+              <ItemsControl.ItemTemplate>
+                <DataTemplate x:DataType="vm:StudentSimpleGradeRow">
+                  <Grid ColumnDefinitions="Auto,*,70,Auto" Margin="0,4">
+                    <TextBlock Grid.Column="0" Text="{Binding DateDisplay}" FontSize="12" Opacity="0.6" Width="80"/>
+                    <TextBlock Grid.Column="1" Text="{Binding CategoryLabel}" FontSize="13"/>
+                    <TextBox Grid.Column="2" Text="{Binding Value}"
+                             IsVisible="{Binding $parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"/>
+                    <TextBlock Grid.Column="2" Text="{Binding Value}" FontWeight="SemiBold" HorizontalAlignment="Right"
+                               IsVisible="{Binding !$parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"/>
+                    <Button Grid.Column="3" Content="Speichern" Command="{Binding SaveCommand}" FontSize="11" Padding="8,3" Margin="6,0,0,0"
+                            IsVisible="{Binding $parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"/>
+                  </Grid>
+                </DataTemplate>
+              </ItemsControl.ItemTemplate>
+            </ItemsControl>
+            <TextBlock Text="Keine Mitarbeitsnote im gewählten Zeitraum." Classes="emptyhint"
+                       IsVisible="{Binding !ParticipationRows.Count}"/>
+          </StackPanel>
+
+          <StackPanel Spacing="6">
+            <Grid ColumnDefinitions="*,Auto">
+              <TextBlock Grid.Column="0" Text="SONSTIGE" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+              <TextBlock Grid.Column="1" Text="{Binding OtherAverageDisplay, StringFormat='Ø {0}'}"
+                         FontSize="12" Opacity="0.7" IsVisible="{Binding OtherAverageDisplay, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
+            </Grid>
+            <ItemsControl ItemsSource="{Binding OtherRows}">
+              <ItemsControl.ItemTemplate>
+                <DataTemplate x:DataType="vm:StudentSimpleGradeRow">
+                  <Grid ColumnDefinitions="Auto,*,70,Auto" Margin="0,4">
+                    <TextBlock Grid.Column="0" Text="{Binding DateDisplay}" FontSize="12" Opacity="0.6" Width="80"/>
+                    <TextBlock Grid.Column="1" Text="{Binding CategoryLabel}" FontSize="13"/>
+                    <TextBox Grid.Column="2" Text="{Binding Value}"
+                             IsVisible="{Binding $parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"/>
+                    <TextBlock Grid.Column="2" Text="{Binding Value}" FontWeight="SemiBold" HorizontalAlignment="Right"
+                               IsVisible="{Binding !$parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"/>
+                    <Button Grid.Column="3" Content="Speichern" Command="{Binding SaveCommand}" FontSize="11" Padding="8,3" Margin="6,0,0,0"
+                            IsVisible="{Binding $parent[ItemsControl].((vm:StudentPerformanceOverviewViewModel)DataContext).IsTeacherMode}"/>
+                  </Grid>
+                </DataTemplate>
+              </ItemsControl.ItemTemplate>
+            </ItemsControl>
+            <TextBlock Text="Keine sonstigen Noten im gewählten Zeitraum." Classes="emptyhint"
+                       IsVisible="{Binding !OtherRows.Count}"/>
+          </StackPanel>
+
+          <Border Background="{DynamicResource SystemControlBackgroundAltHighBrush}" CornerRadius="8" Padding="14">
+            <StackPanel Spacing="2">
+              <TextBlock Text="ZEUGNISNOTE (BERECHNET)" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+              <TextBlock Text="{Binding CurrentReportGradeDisplay}" FontSize="18" FontWeight="SemiBold"/>
+            </StackPanel>
+          </Border>
+        </StackPanel>
+
+        <StackPanel Grid.Column="1" Spacing="16">
+          <Border Background="{DynamicResource SystemControlBackgroundAltHighBrush}" CornerRadius="8" Padding="14">
+            <StackPanel Spacing="8">
+              <TextBlock Text="ZIELNOTE: WAS BRAUCHE ICH NOCH?" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+              <StackPanel Orientation="Horizontal" Spacing="6">
+                <TextBlock Text="Ziel:" VerticalAlignment="Center"/>
+                <TextBox Text="{Binding TargetGradeText}" Width="70" PlaceholderText="z.B. 2"/>
+                <TextBlock Text="in" VerticalAlignment="Center"/>
+                <ComboBox ItemsSource="{Binding TargetBucketOptions}" SelectedItem="{Binding TargetBucketName}" MinWidth="110"/>
+              </StackPanel>
+              <TextBlock Text="{Binding TargetResultDisplay}" TextWrapping="Wrap" FontSize="13"/>
+            </StackPanel>
+          </Border>
+
+          <Border Background="{DynamicResource SystemControlBackgroundAltHighBrush}" CornerRadius="8" Padding="14">
+            <StackPanel Spacing="8">
+              <TextBlock Text="WAS-WÄRE-WENN" FontSize="11" FontWeight="Bold" Opacity="0.5"/>
+              <StackPanel Orientation="Horizontal" Spacing="6">
+                <TextBlock Text="Zusätzliche Klausurnote:" VerticalAlignment="Center" TextWrapping="Wrap"/>
+                <TextBox Text="{Binding WhatIfExamGradeText}" Width="70" PlaceholderText="z.B. 3"/>
+              </StackPanel>
+              <TextBlock Text="{Binding WhatIfResultDisplay}" TextWrapping="Wrap" FontSize="13"/>
+            </StackPanel>
+          </Border>
+        </StackPanel>
+      </Grid>
+    </ScrollViewer>
+
+    <Grid Grid.Row="3" ColumnDefinitions="*,Auto" Margin="0,16,0,0">
+      <Button Grid.Column="1" Content="Schließen" Click="OnClose"/>
+    </Grid>
+  </Grid>
+</Window>
diff --git a/LehrerApp.Desktop/Views/Groups/StudentPerformanceOverviewDialog.axaml.cs b/LehrerApp.Desktop/Views/Groups/StudentPerformanceOverviewDialog.axaml.cs
new file mode 100644
index 0000000..8c1885b
--- /dev/null
+++ b/LehrerApp.Desktop/Views/Groups/StudentPerformanceOverviewDialog.axaml.cs
@@ -0,0 +1,11 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+
+namespace LehrerApp.Desktop.Views.Groups;
+
+public partial class StudentPerformanceOverviewDialog : Window
+{
+    public StudentPerformanceOverviewDialog() => InitializeComponent();
+
+    private void OnClose(object? sender, RoutedEventArgs e) => Close();
+}
diff --git a/LehrerApp.Tests/ReportGradeTargetCalculatorTests.cs b/LehrerApp.Tests/ReportGradeTargetCalculatorTests.cs
new file mode 100644
index 0000000..ce220e8
--- /dev/null
+++ b/LehrerApp.Tests/ReportGradeTargetCalculatorTests.cs
@@ -0,0 +1,81 @@
+using LehrerApp.Core.Models;
+using LehrerApp.Core.Services;
+using Xunit;
+
+namespace LehrerApp.Tests;
+
+/// Tests für die Zielnoten-Frage (Nutzer-Feedback): "Was brauche ich noch, um Note X zu
+/// erreichen?" — Umkehrung von GradingService.CalculateReportGrade.
+public sealed class ReportGradeTargetCalculatorTests
+{
+    private static readonly GradingScheme Scheme = new()
+    {
+        ExamsPercent = 50, ParticipationPercent = 30, OtherPercent = 20,
+    };
+
+    [Fact]
+    public void SolveRequiredAverage_LoestNachDemGesuchtenBereichAuf()
+    {
+        // Ziel 2,0; Mitarbeit 3,0 (30%), Sonstige 2,0 (20%) bekannt -> Klausuren (50%) gesucht.
+        // 2,0 * 100 = x*50 + 3,0*30 + 2,0*20 => 200 = 50x + 90 + 40 => x = 1,4
+        var result = ReportGradeTargetCalculator.SolveRequiredAverage(
+            2.0, GradeBucketKind.Exams, examsAverage: null, participationAverage: 3.0, otherAverage: 2.0,
+            Scheme, GradingSystem.Grades1To6);
+
+        Assert.NotNull(result);
+        Assert.Equal(1.4, result!.Value.RequiredAverage, precision: 4);
+        Assert.True(result.Value.IsAchievable);
+    }
+
+    [Fact]
+    public void SolveRequiredAverage_IgnoriertBereicheOhneBekanntenDurchschnitt()
+    {
+        // Nur Klausuren (50%) bekannt, Mitarbeit gesucht (30%), Sonstige ohne Daten (fällt raus).
+        // Ziel 2,0 nur aus Klausuren(50%, Ø 2,0) + Mitarbeit(30%, gesucht) => Gesamtprozent 80.
+        // 2,0*80 = 2,0*50 + x*30 => 160 = 100 + 30x => x = 2,0
+        var result = ReportGradeTargetCalculator.SolveRequiredAverage(
+            2.0, GradeBucketKind.Participation, examsAverage: 2.0, participationAverage: null, otherAverage: null,
+            Scheme, GradingSystem.Grades1To6);
+
+        Assert.NotNull(result);
+        Assert.Equal(2.0, result!.Value.RequiredAverage, precision: 4);
+    }
+
+    [Fact]
+    public void SolveRequiredAverage_AusserhalbDesGueltigenBereichs_IstNichtErreichbar()
+    {
+        // Mitarbeit bereits sehr schlecht (5,5) -> selbst eine Traumnote in Klausuren reicht nicht für 1,5.
+        var result = ReportGradeTargetCalculator.SolveRequiredAverage(
+            1.5, GradeBucketKind.Exams, examsAverage: null, participationAverage: 5.5, otherAverage: null,
+            Scheme, GradingSystem.Grades1To6);
+
+        Assert.NotNull(result);
+        Assert.False(result!.Value.IsAchievable);
+    }
+
+    [Fact]
+    public void SolveRequiredAverage_BereichOhneGewichtungsanteil_GibtNullZurueck()
+    {
+        var scheme = new GradingScheme { ExamsPercent = 100, ParticipationPercent = 0, OtherPercent = 0 };
+
+        var result = ReportGradeTargetCalculator.SolveRequiredAverage(
+            2.0, GradeBucketKind.Participation, examsAverage: 2.0, participationAverage: null, otherAverage: null,
+            scheme, GradingSystem.Grades1To6);
+
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void SolveRequiredAverage_FunktioniertAufDerPunkteskala()
+    {
+        // Punktesystem: höher ist besser. Ziel 12 Punkte, Mitarbeit 10 (30%), Sonstige 8 (20%)
+        // bekannt -> Klausuren (50%) gesucht. 12*100 = x*50+10*30+8*20 => 1200=50x+300+160 => x=14,8
+        var result = ReportGradeTargetCalculator.SolveRequiredAverage(
+            12.0, GradeBucketKind.Exams, examsAverage: null, participationAverage: 10.0, otherAverage: 8.0,
+            Scheme, GradingSystem.Points0To15);
+
+        Assert.NotNull(result);
+        Assert.Equal(14.8, result!.Value.RequiredAverage, precision: 4);
+        Assert.True(result.Value.IsAchievable);
+    }
+}
diff --git a/TODO.md b/TODO.md
index ad2adbb..c7bdc0a 100644
--- a/TODO.md
+++ b/TODO.md
@@ -221,6 +221,38 @@ Tooltip und nicht sichtbar auf der Kachel — das führte zu Verwirrung, welche
 und wurde ergänzt (`GradeHistoryPoint.Label` jetzt auch unter dem Balken sichtbar, nicht nur im
 Tooltip), siehe [StudentDetailView.axaml](LehrerApp.Desktop/Views/Students/StudentDetailView.axaml).
 
+### 2.6 Leistungsüberblick & Zielnoten-Rechner (Nutzer-Feedback)
+
+Die Zielnoten-Frage ("was brauche ich noch für Note X?") kommt wiederkehrend auf, meist im
+Zusammenhang mit einer frisch geschriebenen Klausur und Blick auf die Zeugnisnote — bisher ohne
+eigenes Werkzeug, nur im Kopf überschlagen.
+
+- [x] **2.6.1** Neuer Dialog `StudentPerformanceOverviewDialog`, erreichbar über den Button
+      "Überblick" in der Notenübersicht der Gruppe (2.1) bei ausgewähltem Schüler — bewusst pro
+      Kurs statt fächerübergreifend, da Gewichtungsschema und Notensystem am Kurs hängen. Zeigt
+      Klausuren (mit Datum, eigener Note), Mitarbeit- und sonstige Noten sowie die daraus mit
+      `GradingService.CalculateReportGrade` berechnete aktuelle Zeugnisnote, Zeitraum wählbar
+      (Gesamtjahr/H1/H2, gleiches Muster wie 2.4).
+- [x] **2.6.2** Zielnoten-Rechner: neuer `ReportGradeTargetCalculator` (Core) kehrt die
+      Zeugnisnoten-Formel um — löst nach dem Durchschnitt auf, den ein gewählter Bereich
+      (Klausuren/Mitarbeit/Sonstige) noch erreichen muss, damit die gewichtete Gesamtnote ein
+      eingegebenes Ziel trifft; meldet ausdrücklich, wenn das Ziel rechnerisch nicht mehr
+      erreichbar ist (nötiger Durchschnitt außerhalb der gültigen Notenskala).
+- [x] **2.6.3** Was-wäre-wenn-Rechner: eine hypothetische zusätzliche Klausurnote eintragen und
+      sofort die sich daraus ergebende Zeugnisnote sehen, ohne zu speichern — deckt den
+      "ich habe gerade eine Arbeit zurückbekommen, was bedeutet das"-Fall ab.
+- [x] **2.6.4** Bewerter-/Schülermodus: ein Umschalt-Button in einem einzigen Fenster (kein
+      getrennter Einstieg) statt zweier Fenster, gedacht zum Bildschirm-Umdrehen im Gespräch.
+      Im Bewertermodus zusätzlich der Kursdurchschnitt je Klausur (Ausreißer nach oben/unten
+      erkennbar) und Bearbeitbarkeit der Mitarbeit-/Sonstige-Noten inkl. Speichern; im
+      Schülermodus ausschließlich die eigenen Werte, rein lesend. **Bewusst nur Mitarbeit-/
+      Sonstige-Noten direkt editierbar, keine Klausurnoten:** eine Korrektur dort bliebe
+      inkonsistent zu `ExamResult.Points`/`TotalPoints` — dafür weiterhin der bestehende
+      `ExamGradingDialog` im Klausuren-Tab.
+      **Bewusst zurückgestellt:** eine Übersicht über alle Fächer eines Schülers gleichzeitig
+      (Gesamt-Zeugnisvorschau) — unterschiedliche Notenschemata/Gewichtungen pro Kurs wären ein
+      eigener, größerer Umbau.
+
 ---
 
 ## 3. Mündliche Mitarbeit — offene Punkte
@@ -370,6 +402,19 @@ Mitarbeit-Note für denselben Zeitraum statt sie zu duplizieren (erkannt über d
       "quantity"-Aspekt mit Skalentyp `Scale5`) — als sichtbarer Vorschlag mit einem Klick zum
       Übernehmen, nie automatisch gesetzt, damit eine bereits vorhandene bewusste Bewertung nie
       stillschweigend überschrieben wird.
+- [x] **3.3.6** Tagesflagge je Schüler/Sitzung (Nutzer-Feedback): "Spitzentag" (👑),
+      "Schlaftag" (😴) und "Schlechter Tag" (⚡) — herausragende Leistungen egal in welche
+      Richtung eindrücklich festhalten, unabhängig von der eigentlichen Aspektbewertung. Neues
+      Feld `ParticipationEntry.DayHighlight` (nullable `DayHighlightKind`, genau eine Flagge pro
+      Eintrag statt kombinierbarer Kennzeichnungen). Primär im Sitzplatz-Dialog
+      (`SeatAssessmentDialog`, ⇧1/2/3 zum Setzen, ⇧X zum Löschen, gleiches Muster wie
+      Anwesenheit/Hausaufgabe) sowie als Badge direkt auf der Sitzplatz-Kachel; zusätzlich als
+      Fallback in der session-weiten Schnelleingabe (`ParticipationQuickInputDialog`, ⇧1/2/3/0)
+      für Lerngruppen ohne Sitzplan. Rein deskriptiv — fließt nirgends in eine Berechnung
+      (Mitarbeitsnote 3.2, Aufrufgerechtigkeits-Quote) ein. **Bewusst noch ohne Diagramm-Anzeige:**
+      die bestehende Notenentwicklung (2.5) zeigt ausschließlich Klausur-/Einzelnoten-Einträge,
+      keine Mitarbeit-Sitzungen — eine visuelle Markierung "im Diagramm" ist erst mit der
+      geplanten Schüler-Überblicksansicht sinnvoll umsetzbar.
 
 ### Abschnittsnoten & Mitarbeits-Assistent (nicht aus dieser Liste, eigener Workflow-Bedarf)