// Methods to implement commands to move and remove students.
 public void MoveStudentToTop(Student student)
 {
     Students.Move(Students.IndexOf(student), 0);
 }
 public void RemoveStudent(Student student)
 {
     Students.Remove(student);
 }
 public void MoveStudentToBottom(Student student)
 {
     Students.Move(Students.IndexOf(student), Students.Count - 1);
 }