One of the things that's really cool about my current job is that I tutor my book's demographic - young teens. Granted, the first book is a bit girlie (which may or may not change in editing). I won't lie. The second however, is much more gender neutral (at least the three chapters I've written so far). I'm not sure what direction it will take.
Still, tutoring has definitely given me an insight I wouldn't have had working elsewhere. Its easy to forget what you thought about when you were 13, 15 or even 18. Life feels very different from that side of 20. Hormones rage, and everything feels as though it is the epitome of an issue, an event, or a relationship. It also feels like it will never end. That perspective of the world is very important when you are writing a young adult novel. It is what makes the story accessible and the characters believable to the reader.