Mayan Equivalent Calculator http://www.michielb.nl/maya/math.html
Coolmath4kids Many things to do here. Try the lemonade stand and see how you do. Or try a brain bender. Don't forget to try many of the math games. http://www.coolmath4kids.com/
FunBrain.com This sight will allow you to do some practicing with skill building in Math and have fun too!At the home page...click Math games. make sure to go to new person and enter your skill level (6 or higher). Then choose a game and have fun! http://www.funbrain.com
Play Deal or no Deal at home! http://www.nbc.com/Deal_or_No_Deal/game/flash.shtml