It is so hard to find good books for a 16 year old. They are either too babyish or too grown up. I wish more writers would do books for 14 to 18 yr olds!
By the way, if you want to introduce a 16-year old to good books, you might want to look into the Mortal Instruments series by Cassandra Clare, Chris D'Lacey's dragon books and The Warriors series by Erin Hunter, which is about cats, are also great. Acorna books by Anne McCaffrey and How to Train Your Dragon by Cressida Cowell are also awesome reads.
Cool, I will have to look into the Warriors. She loves animals. She is going to be a VET when she gets out of high school (she is in the 11th grade this year). She was actually accepted into a local community college this semester to begin some health classes to get her started for major college in a few years. We were excited, just don't like my 16 yr old on campus with college guys!!