Huge teaching tool. My 4 year old has learned basic addition and subtraction! Not only that, but he is reading short words and developing a willingness to try new things.
It is easy to travel with.
The games can be found easily and on sale frequently.
All games work and there is a large age span with the games.
Games have several levels so they can be used by different kids at the same time.
We have experienced our Leapster randomly shutting itself off.
My nephew had one where the screen went half blank, and a second where the buttons stopped working. Leapster is replacing it without argument and free of charge.