I borrowed this from the library, then bought it for my teen, then bought my own copy, then bought one for another adult. That's how good this is. Clear, direct explanations of Buddhist concepts without oversimplification. (Hard to do, right?) Explains suffering, ethics, and meditation in a teenage context, but doesn't spoon-feed or promise quick solutions (takes the veeeery long view natural to Buddhism). The book should be compelling to teens because of this honesty and because it puts the teenager at the center of the struggle, the decisions, and the life that gets formed and re-formed from them. At the same time, the examples all worked for me as an adult. (Generally, how to deal with impulses of all kinds while trying not to hurt oneself or others. When do we get to be done with that?)
You couldn't do better for an introduction to Buddhism at any age, but for a teen--wow.