How old is the kid in question? If they're a pre-schooler, Fisher Price makes a decent digital camera (I don't have kids myself, but this is what my friend tells me, she has two preschoolers, and they haven't managed to break it yet).
If the kid is much older than seven or eight and is fairly responsible, you're probably better taking ChrisA's advice and getting a "regular" camera second hand, either off eBay or perhaps at a local camera shop or second-hand retailer, and let him/her experiment with that.