After reading the letter he wrote to his principal (included below because HN won't allow an Ask HN post over 2000 characters) I think I am going to disappoint his parents and recommend that as soon as he gets his GED that he go ahead and drop out.
Any advice / thoughts / concerns / considerations anyone could provide would be greatly appreciated.
It's definitely a goofy, pompous, rambling letter written by someone who doesn't know what he doesn't know yet. But assuming the business is profitable, there's zero chance that you or his parents can stop him from pursuing it at this point. I think this 15-year old's decision is made, and the point to intervene might have been when he started employing people.
I wasn't particularly academic, but wasn't driven / confident enough at college to start a business either. So I got my grades, degree etc. first, and have never given a CV to anyone. But I think anyone who gets that far, got through education to 18 or 21 and says they got nothing out of it years later is pretty stupid or short-sighted.
A year of computer science at college turned me from a know-it-all hacker into a grateful know-nothing. Two years of classics before that showed me how to spot when I was hopelessly bored and only trying to fulfil others' expectations, while I built a great relationship with my wife. You get something out of such a dense set of life experiences, but you might have to work it out what it was afterwards.
I'd say to the parents let him go, with a stern & overblown warning that he'd better not fuck it up. If he's burned out or bored of the hosting business at 17 or 18, there's nothing stopping him from resuming his education if that's what he wants - it's just doing things in a different order.