Looking for some great gift birthday ideas for 9 year old boy can be a daunting task. You need to find out what he’s really into and go from there. If your nephew is intrigued by science or you simply want to buy him reading material that’s educational as well as entertaining, check out our 10 top science book picks (a book from this list would go well with the Disgusting Science Kit above). If he’s a big sports fan, you may be able to find a book about a famous player.