I just finished this book - the Core realities of youth ministry by Mike Yac -
Fantastic book - I am going to use it this fall in developing what a discipled person in our youth ministry looks like. It is a yout hministry book, not a devotional or spiritual living book, so it's not really for everyone to go out and buy - it is for YP's who want to bring their youth ministry to the generation instead of forcing the generation to conform to a modern version of the gospel.
His core realties are:
foundation - the Bible (good start!)
It's good stuff - if you are a YP you will be encouraged and entheosed (excited by God) after and during this book.