If there is the time show him/her how to write a fun but simple game or star with something already written that you can explain to them how its written and how

If there is the time show him/her how to write a fun but simple game or star with something already written that you can explain to them how its written and how they can change the code to make it do other things (changing formulas, variables/graphics, etc.) I got into programming partly learning how to program, but also experimenting by hacking up BASIC games, it was fun to change the rules, and or actions in the game, and energized my desire to learn to write my own.