Smart Apps for Kids, is one dad's quest to find the best educational apps for the iPad and iPhone (no joke it says it right there on the site 8-). This is an excellent site for finding apps by different age levels. Best of all is how easy it is to use and the star rating system is top notch.
I highly recommend checking out Smart Apps for Kids by clicking here!!!
For other great app finding sites check out Mind Leap and Appitic.