This CARS book by Leap Frog for My First Leappad is alot of fun. Of course it is licensed by disney and is similar to the movie, having all the main characters in it. This book is for kids from 3-5 and I think it fits those ages well.
The book teaches different skills on the different pages such colors, numbers, the alphabet and more. I really enjoy that it reinforces what kids need to learn in a fun way. It is also a storybook, that is read to the child electronically. We gave our son his for his 1st birthday and have used it together for many years (4 now). At one he couldn't do it by himself, but was happy to sit and listed and use the pen stylus to touch different pictures and hear what they were.
On each page is also usually a little game to play, they vary page to page. This is double sided pages so had alot to offer. It does need the cartridge to play (comes with the book) so we just keep all together in a little bin. They also sell backpacks for keeping them organized. I would highly recommend my first leappad CARS book.