Four Seconds - A timer and a simple rule: stop it at exactly four seconds.
MathIsFun Times Table - Learn Your Multiplication Tables
Wikids - An encyclopedia that talks to your kids
I Know It - "I Know It" is an online game for practicing primary-level math concepts.
DragonBox Numbers - Teach kids about numbers with an easy and fun game
GCompris - Educational Game for Children 2 to 10 years old.