The Factor Tree

I recently tried this site out with my little brother. I received a free trial via BzzAgent.I sat down with him to do the evaluation test. It was very easy, and he was able to continue playing around the on the site by himself. Factor Tree seems like a very effective learning tool because it makes math fun, which causes kids to be more interested in it. I think it would be extremely useful for those kids whose weak point is in math. It is also a great tool for parents since it sends a feedback report of the child's progress.
I have recommended the site to the parents of some of my brother's friends!