Here is a really good children's picture book that my 21/2 year old happened to find in the library. I think she liked the bright orange cover. It has become a favorite read of ours for the 3+ weeks we have had it checked out. "Humphrey, Albert, and the Flying Machine" by Kathryn Lasky is loosely based on the tale of Sleeping Beauty, only from a boys point of view. Daniel Bernoulli saves the day with his amazing flying machine and a little lesson on how 'lift' occurs. In this story it is not looks but smarts that saves the day.
I highly recommend it. Even my girls enjoyed although I probably woul have considered it a 'boy' book. MB really picked up on the parallel to Sleeping Beauty. It moved on to us making paper airplanes and discussing wind flow and how planes vs. helicopters fly.