Literally, each character, save for Abner whose attempts to take over as principal are thwarted by the progression of all the characters and the timely return of Principal Paulson, reaches a point in their life where they seem happy with themselves, their relationships with their friends and their relationships with their parents.
Figuratively, each character, except Abner, who is thwarted in his efforts to assume leadership by the development of all characters and the timely return of Principal Paulson, reaches a point in their lives where they appear content with themselves, their friendships, and their relationships with their parents.