(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/
Math http://www.kidskonnect.com/MathSites/MathSites.html
http://www.funbrain.com
http://www.macmillanmh.com
http://www.aaamath.com
Language Arts http://www.harcourtschool.com/menus/language_arts/grammar_park_g3.html
Language Arts http://www.sadlier-oxford.com/vocabulary/levels_color.cfm?sp=
http://baip.elearndesign.org/
Spelling http://www.spellingcity.com