(Sample link) White House for Kids http://www.whitehouse.gov/kids/whlife/index.html
(Sample link) National Geographic for Kids http://www.nationalgeographic.com/kids/
A variety of educational games and activities http://www.funschool.com
Educational games and activities: math, science, language arts... http://www.funbrain.com
Crafts and Projects for a Family Fun Night http://www.familyfun.com