One of the most important lessons (in my opinion) I attempt to teach my students has to do with allowing people to do whatever they are going to do, sitting back, and watching them self-destruct. You can not control the world, or the events that are happening outside of you so you deal with what you can control: your own behavior. How one reacts to a situation speaks volumes about who that person is.
I understand what a difficult concept this is for teenagers. Especially since I watch adults go through situations time and time again where they should be able to have some self control, yet don't, and not learn anything. It is something we work on in class daily, and if only one student gets it... not even now, maybe even sometime in their 20s.... I will have taught an important and valuable lesson.
Yes, I know, I'm supposed to be teaching Math & English, but really, isn't personal responsibility and self-control just as important?