We know teenagers behave in mysterious ways. Their ups and downs are usually attributed to hormonal changes. But neuroscientists now tell us that the brain goes through significant growth spurts during the adolescent years, getting reshaped in a developmental phase as important as those of early childhood.

This fall, Barbara Strauch, health and medicine editor for The New York Times, will teach an online course entitled "Exploring the Teenage Brain," a course that is part of the New York Times Knowledge Network and open to consumers nationwide.

The three-week course will cover

• What the latest science tell us about important changes in the brain
  How this new learning connects with what we already know about hormones and other influences on teen behavior
  Why alcohol, smoking, and drugs are especially dangerous to the teenage brain
  Why erratic or even hostile behavior can often be normal, however unpleasant
  Why sleep is so important for teens
  How parents, teachers, friends, and adults can cope with this awkward period in a child's life.

The facilitated course runs September 26 - October 16, 2011 and costs $110. The self-paced version has a rolling admission and costs $85. You'll find more information here.