Well your ds sounds a lot like my ds & I guess we just got lucky w/the elementary he was in, they realized early on (he was already finished 1st & bored in pre-k) that he just HAD to have other things to do.
So most of his years there the teachers or principal would give him other things to do ...help the other students,work in the office or the library. His 5th grade year he worked in the office & library more than he was in his classes.
Academically Advanced Charter schools have been our saviors since ...he just has to be challenged & respected or he just won't co-operate. I can't even tell ya how many nights he would work on a project for hours,only to NOT turn it in & get a zero the next day. His usual excuses were like "I don't know why" to "she hates me & was going to fail me anyway". We went
thru several teachers that pre-judged him & felt like he ought to "just sit & wait for the class to catch up" !! And They always tried to bull dog me into "making him do it " ...yeah right ... Just drove me crazy !!! But once we found a school where he was comfortable & felt understood,everything was/is great.
He is the 11th grade now & is only going to H.S.in the am, then he goes to a tech school where he is earning college credits ...he had taken all the classes he had any interest in the last few years, so the tech school deal was the only way I could see that we might keep his interest long enough to get his H.S. basics done & graduate . And he will have 27 credit hrs done when he moves on to college too.
He has always been academically advanced ,but very immature for his age. So we never wanted to test out of grades either.
I don't know how big of a city you live in but it might be worth looking around for a Charter or Magnet school that is advanced enough to HELP him realize his potential & hold his interest .
The one he is in now is Fine Art based & they seem to totally understand him. I am glad someone does ....cuz I still don't quite get it.

I hope my babbling helped ya' somehow ......