Don't know if the legal age to drive varies, it very like does though as I'm pretty sure all driving privileges are regulated at the state level.

The training does differ widely by state. Age is a criteria in at least some; I know in MN it is not required at all for adult applicants. Just have to pass the written, eye, and road tests. And at least in some states, a training course used to be paid for as part of a High School education. Where I went to school, it was an elective in the curiculum, and most everybody took it as soon as they turned 15 1/2. Passing gave you a 6-month learner's permit, and at 16 you could take the test for a DL.

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Don of Borg - Cool, Calm, Collective.

"Within the next generation I believe that the world's leaders will discover that infant conditioning and narco-hypnosis are more efficient, as instruments of government, than clubs and prisons, and that the lust for power can be just as completely satisfied by suggesting people into loving their servitude as by flogging them and kicking them into obedience." -- Aldous Huxley