I think the OP’s question is more complicated regarding EC’s. I disagree with other posters that colleges don’t care about them. I think some colleges don’t care, and some colleges really really care. For instance, the more elite colleges expect applicants to meet a benchmark for grades and stats but then it really is all about EC’s or talents and how the applicant can contribute to an interesting mix for the class as a whole.
So, it depends on what colleges you are applying to. I think, in general, the larger places, including state universities, are by necessity more driven by grades and scores.
One of mine didn’t do high school at all in senior year, and was a middling student, but had a talent she pursued as an EC and then in place of school entirely. She got a GED. College admissions told me they loved “outliers” like her.
I know a young man who struggled emotionally in senior year, who took a year off, did a wilderness program for a few months, and got in to some great schools as a result.
Anything that makes a kid interesting- collecting butterflies!- helps with admissions, but one hopes it is also a sign of a happy life while pursuing interests.
Do I think this applies to the OP’s child? No! It sounds like this is a hard-working kid who has overcome some challenges- another thing colleges love- and done well. And there are many colleges that will completely respect that. And there are many colleges that DON’T use EC’s as an important criterion.
I think that this young person can apply to various schools (Colleges that Change Lives?) and do well with admissions.
I also think there are many reasons to consider a gap year if that is what the parent and child want. Are there ways to make that year a help in preparing for a transition, or would it be a step backward? What ideas does the parent have for that year? (google NOLS for wilderness program ideas). Are there programs for the purpose of transition and preparation? (Landmark College has one I believe.)
How does the OP feel about a school program that focuses on kids on the spectrum? Do you prefer that he stay in the mainstream? What supports are needed? Would you want him close, or move near him?
I agree with everyone that he will do fine with admissions and could head to college next year. But when you say he can go by himself, it raises questions, and the idea of a gap year has merit for reasons having nothing to do with EC’s.
We have no idea where he lands on the spectrum so to speak, but clearly he is very capable academically, and has a caring parent who will make the right decisions with him!!
ps there are other options: I know a kid with a similar challenge, who used community college for transition; he met weekly with someone who supported and advised him and did very well. He then transferred. I forget if he did community college for a year or two, but he got a lot of gen eds done that way and learned to be more independent of parents. Another option, which one of my kids w/ADHD does, is to take only a couple of classes and do an EC or work. Best of both worlds, for a time, until the path is clear.