Being 16 myself, I can also recommend the ESPN Zone in Downtown Disney if she's into sports. Though, I'm not a girl, I know that they like to shop, so just spending some time in DTD might be fun for her. I
n addition to what PinkBudgie said, I also recommend Soarin (although your sig shows that you've been to WDW several times, so I don't know about that one), Indiana Jones! (amazing thrill ride that isn't at WDW either), and Big Thunde Mountain.