Teenagers are at a developmental stage where getting distracted is more problematic than it is for older drivers. They are still developing the ability to regulate their attention and emotions so they can function well under challenging circumstances, says Daniel Keating, a professor of psychology at the University of Michigan who has published studies on the effect of adolescent development on driving.
On teaching about the dangers of driving while distracted:
http://www.kare11.com/news/article/986123/396/Driving-advice-for-parents-put-your-phones-down
And Some new stricter laws regarding teens driving with other teens in the car:
http://parenting.blogs.nytimes.com/2012/08/14/increasing-limits-and-safety-for-teenage-drivers/
And how to asses if your teen is ready to drive:
And new technology to monitor your teen’s driving:
http://www.usatoday.com/story/news/nation/2012/10/19/parents-monitoring-teen-driving/1638475/