The reason why I think 16 year olds should be able to drive is because their parents aren't going to drive them everywhere. Also, I think a sixteen year old is responsible enough. And also they could car pool to school with their friends.
First off, their parents can't drive them everywhere. They had to when they were born until they were 15 years old. Also this way they won't be embarrassed when riding with you parents.They are older so let them drive.
Secondly, they are responsible. Just let them drive! They may do something irresponsible every once in a while, but who doesn't do something irresponsible. I mean they have matured a lot. So just relax most teens can handle themselves, but there are some exceptions.
Finally, if you would let them drive they could car pool. Then they could get to school faster and safer because there wouldn't be as many cars. If every one drove their own car, it would be like New York City at 5 p.m.
So for goodness sake just trust them and let them drive, but maybe not your $50,000 car. But still if you can trust them let them. How can they get more responsible if you don't let them gain more trust.