Here comes the librarian: LOL
DD is reading Esperenza Rising. On her "to read" stack sits Molly Moon's Incredible book of Hypnotism and Olivia Kidney
She also loves the Princess Diary series and anything by Tamora Pierce. She just finished the second Sisterhood of the Traveling Pants.
Other teens at the library are reading (in addition to Potter)
Artemis Fowl, the Sammy Keyes mysteries, the Redwalls, Love Among the Walnuts, and anything by Gary Paulsen.
Good Luck, keeping teens reading is my full time job and it's not easy!