Here's our favorite multiplication game:
You'll find a FREE version and a paid version. We started out with the free game and loved it so much we later upgraded. If you do decide to upgrade be sure to do a Google search for coupon codes for TimezAttack! We found one last year that saved us $10!
UPDATE: Big Brainz now has a division game! My 10 year old gives it two thumbs up.
If you purchase Timez Attack, you'll be able to download the game to all your family computers. If you have to reinstall windows (ever been there?), you'll be able to access your account and download the game again. We recently found this out when my laptop caught a nasty virus. I simply logged onto my BigBrainz account and downloaded the game I'd purchased an entire year ago. The new download included the basic division game! Pretty sweet.