static void Main() { var someSchool = new School(); var eveningClass = new Class("Level#2"); var trainer = new Teacher("Mr. NakMan"); var disciplineClassA = new Discipline("OOP", 2, 2); var firstStudent = new Student("Anamalech", 1); var thirdStudent = new Student("Corson", 3); var secondStudent = new Student("Boruta", 2); var forthStudent = new Student("Lucifer", 4); //Okay. Let's summon the demons... pardon, Demos! someSchool.AddClass(eveningClass); eveningClass.AddTeacher(trainer); trainer.AddDiscipline(disciplineClassA); eveningClass.AddStudent(firstStudent); eveningClass.AddStudent(secondStudent); eveningClass.AddStudent(thirdStudent); eveningClass.AddStudent(forthStudent); Console.WriteLine(eveningClass.ToString()); Console.WriteLine(); }