A while back I wrote an article about Kids and Usability. It's Part 1 of 3 (though to be honest, I've only written two of the parts.)

Developing websites for kids poses and interesting challenge, and one which is best met by a passionate and highly skilled interdisplinary team.

This article covers some of the basic "rules of the road" when developing sites for kids. The next part covers a specific example of a site I recently helped develop.