Mr. Saganiec's Earth Science Homepage http://www.ezclasssites.com/mr_saganiec_science/
Math.com http://www.math.com
Worksheets for the basics - APlusMath http://www.aplusmath.com/Worksheets/index.html
More Math Worksheets - Math-drills.com http://www.math-drills.com/
Math Games - Gamequarium http://www.gamequarium.com/math.htm
More Math Games and puzzles - coolmath4kids http://www.coolmath4kids.com/
Games, Problems, and Puzzles - Math Playground http://www.mathplayground.com/games.html
Number puzzles to think a little different! Try them out. http://www.smart-kit.com/scategory/brain-teasers/lateral-thinking-puzzles/
Cool Math Sites http://cte.jhu.edu/techacademy/web/2000/heal/mathsites.htm