I really appreciate the emphasis on friendships and courage. When Mallory is sent to Earth on a mission to help Phoebe, Mallory comes all the way from the land of Faeries, but she must learn the ways of humans in order to befriend Phoebe and complete her mission. We see their friendship develop all through junior high and then things start to get very complicated when Mallory's brother shows up. This book does challenge you to think about what is important to you - I always like that in a book - especially for teens! It is just a great read - it is so intriguing that it keeps you enthralled from beginning to end.
The other thing I loved about this book is the Jewish protagonist - what a fun twist from what I normally read. I like glimpses into other cultures and this novel provided that as well. I would highly recommend this book - even compared to other YA, this book is fairly "tame" in content. There were mentions of sex, or places where it was alluded to, but the one that stands out to me is where the teens decide not to go through with it - so that helped to keep it's tame rating intact!