Although Percy Jackson and the Olympians—The Lightning Thief by Rick Riordan is often billed as a great book for boys (which it is) my daughters have also loved it. I’ve seen it with both girls (separately since my oldest daughter is now away at college), and they both enjoyed it. Here’s a review from a mom and her son who both read the book and went to see the movie as well. It was featured on 5 Minutes for Books. You’ll also find a great post about it (as noted in the comments here) at Pragmatic Mom.