I would also like to point out, that even if he won't drive a mile in all those years, if you wait until 18 or even later, you will be in all the hassle of college, perhaps even working, and all that, sometimes even moving to another state to study, which makes it a million times harder to get a license, because you have got less time to be around taking tests, driving school and so on. You can do all that in summer vacation, and weekends as a teenager when you've got nothing else to do and then when you really need the license you will already have it. We are not even starting to talk of how important is to know how to drive, even when you normally don't need to - if he finds himself in an emergency where he has to drive a car, and he doesn't even know where is the pedal sitting, much less even have a learners permit?
Down here, they always try to stress also, that if you are planning to study in the states, getting a PR license before you go, is a must. In the 50 states, license requirements are often stricter and higher than in Puerto Rico, and you have to wait much longer amounts of time between the learners permit and the license. In some, you might even have to get driving school (unheard of down here). If you already have the PR license, which is a million times easier to get, you can in almost every state of the union, bring it to the DMV as an out of state license, file as a new resident, and change it for an in-state license, saving you most, if not all of the hassle.