http://en.wikipedia.org/wiki/Driver's_license_in_the_United_States
You can get your license at the age of 15 in the following states:
Idaho
Kansas
Montana (ranked 4th highest)
New Mexico (ranked 11th highest)
South Carolina (ranked 8th highest)
In North Dakota (14th highest) and South Dakota (9th highest) you can get your DL at the age of 14!
In New Jersey you have to be 17 (5th lowest), and in many of the Northeast states, you have to be 16
and 6 months.
I know it seems trivial, but maybe those additional 6 months could possibly save several lives.