The Adolescent mind
While adults think with their frontal lobes, teenagers think with their amygdala. What is that, you ask? Well, it's one reason that teenagers seem to lack impulse control. The amygdala is not highly advanced when it comes to self control, and the teenage brain is constantly being flooded with new hormones and instincts. In the adolescent stage, peer recognition matters the most; more than it ever will in any other stage of life. The reason that teens try so hard to achieve peer acception is because of this. They find the most novelty in eachother.
Teenagers tend to seem reckless because they take more risks. In reality, teenagers aren't just reckless, but they value the reward more than they acknowledge the risks of their actions.
It used to be thought that the brain had completed development in elementary school, but now that more research has been done, we have found that the adolescent stage plunges us into extreme chemical and emotional development.
"Series of scans of the developing adolscent brain...showed that our brains undergo a massive reorginization between our 12th and 25th years."
-National Institute of Health