Cool Math 4 Kids
This is one of the coolest and kid friendly math web sites on the internet. I cannot even come close to describing all that they offer but the thing that makes it most unique is how kid friendly it is. A child who doesn’t understand decimals can easily walk through the section dedicated to it without any adult help. The only skill he would need to learn a math lesson is the ability to read fluently.
In addition to all of the elementary skills it covers there is also information on geometry, algebra and calculus. This is such a wonderful learning tool that you will want to add it to your favorites list.
Check it out - http://www.coolmath4kids.com/