Cherry Heaven by L.J. Adlington is the companion novel to The Diary of Pelly D (which I haven't read). This sci-fi mystery was suspenseful, dark, and entertaining. You know from the first sentence that everything is not as perfect as it seems.
"the last birthday i ever had, years ago, was the one where i got shot instead of presents."
For fans of Uglies (Westerfeld), City of Ember (DuPrau), House of the Scorpion (Farmer). Other titles to try Avielle of Rhia (Calhoun) and The Adoration of Jenna Fox (Pearson).