Project: Student Management System in Dart

Project Goal

Build a student management system that tracks students, their grades, GPA, and generates class reports. This project covers OOP, collections, sorting, statistics, and data formatting.

Design

• Grade record: subject + score
• Student class with GPA calculation
• StudentManager with CRUD, search, rankings
• Report generation

Full Code

class Grade {
  final String subject;
  final double score;
  Grade(this.subject, this.score);
  String get letterGrade {
    if (score >= 90) return 'A';
    if (score >= 80) return 'B';
    if (score >= 70) return 'C';
    if (score >= 60) return 'D';
    return 'F';
  }
}

class Student {
  final int id;
  final String name;
  final int age;
  final List<Grade> grades = [];

  Student({required this.id, required this.name, required this.age});

  double get gpa {
    if (grades.isEmpty) return 0.0;
    return grades.fold(0.0, (sum, g) => sum + g.score) / grades.length;
  }

  String get gpaGrade {
    var g = gpa;
    if (g >= 90) return 'A (Distinction)';
    if (g >= 80) return 'B (Merit)';
    if (g >= 70) return 'C (Pass)';
    if (g >= 60) return 'D (Borderline)';
    return 'F (Fail)';
  }

  void addGrade(String subject, double score) {
    if (score < 0 || score > 100) throw RangeError('Score must be 0–100');
    grades.add(Grade(subject, score));
  }

  @override String toString() =>
      'Student($id: $name, Age: $age, GPA: $${gpa.toStringAsFixed(1)} $gpaGrade)';
}

class StudentManager {
  final Map<int, Student> _students = {};
  int _nextId = 1;

  Student add(String name, int age) {
    var s = Student(id: _nextId++, name: name, age: age);
    _students[s.id] = s;
    return s;
  }

  Student? find(int id) => _students[id];

  List<Student> get all => _students.values.toList();

  List<Student> get ranked =>
      [...all]..sort((a, b) => b.gpa.compareTo(a.gpa));

  List<Student> search(String query) =>
      all.where((s) => s.name.toLowerCase().contains(query.toLowerCase())).toList();

  void report() {
    if (all.isEmpty) { print('No students.'); return; }
    print('\n===== CLASS REPORT =====');
    print('Total students: $${all.length}');
    var gpas = all.map((s) => s.gpa).toList();
    var avg = gpas.reduce((a, b) => a + b) / gpas.length;
    print('Class average GPA: $${avg.toStringAsFixed(2)}');
    print('Highest GPA: $${gpas.reduce((a, b) => a > b ? a : b).toStringAsFixed(2)}');
    print('\n--- Rankings ---');
    var r = ranked;
    for (var i = 0; i < r.length; i++) {
      print('$${i + 1}. $${r[i]}');
      for (var g in r[i].grades) {
        print('   $${g.subject}: $${g.score.toStringAsFixed(1)} ($${g.letterGrade})');
      }
    }
  }
}

void main() {
  var mgr = StudentManager();

  var alice = mgr.add('Alice Johnson', 20);
  alice.addGrade('Math', 95.0);
  alice.addGrade('Science', 88.5);
  alice.addGrade('English', 92.0);

  var bob = mgr.add('Bob Smith', 21);
  bob.addGrade('Math', 72.0);
  bob.addGrade('Science', 68.0);
  bob.addGrade('English', 75.5);

  var carol = mgr.add('Carol Lee', 19);
  carol.addGrade('Math', 98.0);
  carol.addGrade('Science', 94.0);
  carol.addGrade('English', 96.5);

  mgr.report();

  print('\n--- Search: "smith" ---');
  mgr.search('smith').forEach(print);
}

Challenges

• Add course credit weights for weighted GPA
• Add export to CSV
• Add attendance tracking
• Build a Flutter UI with charts for grade visualization