You get them to figure out and write out the logic to pong. On paper. Then graduate them to actual programming, and help them along a bit. Tell them to experim

You get them to figure out and write out the logic to pong. On paper. Then graduate them to actual programming, and help them along a bit. Tell them to experiment with pong when they get it going. Add more paddles. Add more balls. Add obstacles. Add whatever they think would be cool. A Richard Garriott has talked about, good game design is a critically difficult field. Get them experimenting with gameplay as related to the underlying engine before you ever push them to a game design school.