Kirsten Hubbard's Like Mandarin
In this book, the typical smart kind of outcast girl is befriended by the older bad girl at school, while also having to deal with her pageant-obsessed mother and her talented little sister. I didn't buy the friendship at all--the bad girl was such a crazy brat that no one would ever actually be friends with her--and thought the end resolved much too easily, but I did like the little sister character a lot. Kind of a disappointing read when it was blurbed by Melina Marchetta, though. B-.