J.P.
We have 4 kids, homeschool and my husband and I work, so we use the computer a lot of time for homework. My 3 year old daughter finished the state standards for Pre-K math and is on to K math. The kids ASK to use IXL for math. My 9 year old is in 5th grade and has found he loves Geometry and Algebra. Here's some ideas. If you want more, feel free to contact me.
http://www.enchantedlearning.com/Home.html - $20/year unlimited worksheets. This is my favorite site.
http://www.ixl.com/ - math and it's $79/year/1st student + $20/year/addt'l
http://www.handwritingworksheets.com/ - FREE worksheets
http://www.homeschoolmath.net/ - FREE worksheets
http://www.spellingcity.com/ - FREE SPELLING GAMES
http://www.learninggamesforkids.com/ - FREE GAMES
http://www.goodtyping.com/default.htm - FREE TYPING (I learned to type in 2nd grade)