You might want to look at the Aluratek Libre Pro or the Etaco Jetbook. They use a reflective LCD screen, which while slightly grayer than the e-ink screens, are still eminently readable. I think the screens are sturdier on those. My 2 year old nephew is fascinated with my "books" (as he calls them) and he has dropped the Aluratek a few times on a hardwood floor and it has survived. My Sony I only let him play around with when he's sitting on his bed.
An ebook reader is a cool gift for a kid, and I can understand your reasons for getting one. My 5 year old niece wants one after seeing mine. But I've decided not to get her one anytime in the near future, mainly because it's not something that she would be using in school, and IMO, the under-12 age group needs to learn how to navigate paper books, how to use an actual dictionary (because looking up words in a paper dictionary introduces the reader to new words as they search out the one they want, something that doesn't happen with the electronic versions), how to take notes in long hand rather than by just highlighting and copying, and to appreciate the actual physical aspects of books with all their variations.