Here are a few downloads available for your childs education. TimesAttack is a fun multiplication game that enhances your childs math skills. Chase dangerous monsters, wind your way through dark tunnels - all while you learn your multiplication! Times Attack is a first person shooter game where you use math to fight your opponents instead of weapons. I purchased the full version because she enjoyed it so much and the graphics were great! Their is a free version available.
Also for your pre-K and Kindergarden children, introduce them to letter phonics, and reading skill at Starfall. (Thanks Utahdealdiva)