Some recommendations:

* http://www.chesskid.com/
* http://www.amazon.com/Learn-Play-Chess-Fritz-Chesster/dp/B0000950SM
* http://www.amazon.com/Chess-Childre...mp;ie=UTF8&qid=1302814620&sr=1-1

For a while DS (then 6?) was hot on chess. Not as much these days. But he used those resources as well as attending a chess club occasionally.

Good luck.

JB