Brain Pop (Science)
http://www.brainpop.com/
Discovery Education (Science)
http://www.discoveryeducation.com/
Mr. Nussbaum's Math Games
http://mrnussbaum.com/gamescode/
Math Blaster
http://www.mathblaster.com/parents/math-games/3rd-grade-math-games
Fun Brain (Math)
http://www.funbrain.com/FBSearch.php?Grade=3
Reasoning Minds (Math)
http://www.rmcity.org/
Cool Math
http://www.coolmath-games.com/spelling-monster/third-grade-3/index.html
Zoodles (Social Studies games)
http://www.zoodles.com/free-online-kids-games/third-3rd-grade_social-studies/
http://www.brainpop.com/
Discovery Education (Science)
http://www.discoveryeducation.com/
Mr. Nussbaum's Math Games
http://mrnussbaum.com/gamescode/
Math Blaster
http://www.mathblaster.com/parents/math-games/3rd-grade-math-games
Fun Brain (Math)
http://www.funbrain.com/FBSearch.php?Grade=3
Reasoning Minds (Math)
http://www.rmcity.org/
Cool Math
http://www.coolmath-games.com/spelling-monster/third-grade-3/index.html
Zoodles (Social Studies games)
http://www.zoodles.com/free-online-kids-games/third-3rd-grade_social-studies/