Here in Ohio, if the driver is under 18, there can be no more than one passenger under 18. Something about distractions.
Personally, the way I see it, the earlier you start driving, the better you can become. It gets ingrained in your still-maturing brain, the whole concoction just has to be nurtured along the right way. If you start driving well into adulthood, you may have a brain that is no longer developing, and now has no high-speed experience to reflect upon. (the decision-making center of your brain continues to develop well into the early-to-mid twenties)
Now, if it's handled wrong from the start, the brain may learn terrible decisions as having been correctly handled, but if handled right, it can nurture the development of important experiences that will set an individual on the right path to good-driving.
Of course, it might be rare that someone ends up a good driver when they are an adult... fuck, we all know how rare the good-driving species has become.
Think how often teens make mistakes - I say, you really cannot become good at anything, until you learn from mistakes. If you get away with never making a mistake, eventually you'll find yourself in a situation where experience is necessary, or an abundance of amazing luck.
If you make mistakes during the best time to make mistakes, when your brain is still developing/maturing, you have a better chance of coming out on top. That is, if you find out how to teach yourself most effectively.
Teen drivers make mistakes, but they really have to make them sometime. And the parents will say, a good mistake is one where nobody gets hurt and the driver learns. Hopefully that little punk learned.
I had lost control numerous times, in a few different conditions, and escaped physical injury or vehicular damage. Sometimes it takes a few "oops" to really learn the ins-and-outs of a specific vehicle, which is something that you must know imho; not knowing every single little piece of information about your vehicle, at least in terms of how it performs and controls, is asking for serious trouble. You should know how to translate the language of the steering wheel into knowledge of exactly what the wheels are doing, for instance. Then again, some factory decisions, like the level of dampening in the shocks and specifics of the automatic steering system, can make this extremely difficult on some vehicles; if you can't feel potholes, you can't accurately judge your state of grip.