Depending on the age of the child you might want to look at unity3d. It's a game writing environment. Perhaps you're looking at kids 9 or over for this. My thi

Depending on the age of the child you might want to look at unity3d. It's a game writing environment. Perhaps you're looking at kids 9 or over for this. My thinking is the kids will be super interested as they can write a small game and the environment is complete and free with lots of tutorials.