In my year of working at a wilderness camp with at-risk youth, we were taught to identify negative behaviors through one of four psychological needs: love, power, freedom, or fun. Honestly, this pretty much covers every psychological need of humans.
Anytime one of my students was acting out, if I could identify the need that was not being met, it was not long before the behavior could be corrected. Then, of course, the ultimate goal was to get the kids themselves to identify exactly what they needed.
To break them down into a little more detail for you:
Love: affection, appreciation, personal attention (often this was lacking from home/family first and was difficult to establish in a counselor/student setting. The "love" need was easier to meet with campers I'd had for several weeks or months.
Power: independence, the need to be heard and listened to, the need for control of something. Providing choices as well as giving kids input in what direct the class (or therapy) is going helps this need.
Freedom: similar to power, the need to be independent. I think this is a general need for all adolescents and isn't fully met until they get out of the house and on their own.
Fun: exactly how it sounds, the need for recreation, laughter, humor, play-time.