C.M.
We bought the Barbie Laptop for my 4 year old years ago, and my kids 9 & 10 still get it out from time to time. There are lots of learning games on it. Check out anything by Leapfrog, as well.
When my daughter was in Kindergarten I bought her the leapster (more like a video game than a laptop) and a few of those cartridges and she played with that until she got a nintendo ds in 3rd grade.