I have one who does not "fit in".
Academic derby or the debate team.
math team
sports, my daughter does swimming, it's individual but you're still on a team.
Does he play an instrument, violin, trumpet? Look into the band and orchestra, if he plays piano look into the jazz band.
Chess club
Robotics Club
FFA
FBLA
Engineering club or society
Does he want to move? We moved right before my son's senior year and again before my daughter's junior year. (military) Not good.
The only school I would move him to would be a math and Science academy, usually those are boarding schools, IMSA is one in Illinois. There is one in Raleigh, but for NC students Michigan should have one.
Is he taking courses that are challenging, Engineering, AP, Dual Enrollment?
Does he want to fit in? Or does mom want him to fit in more?
1000 students is really small. Our last four high schools were all around 1200-1400. As a sophomor, my daughter knew almost every sophomore, junior, and she is not social.
Extremely smart kids sometimes don't know how to fit in. Changing schools just teaches them that if they run into problems in life then it's OK to run away from them.
Maybe have him take community college courses at night and graduate with an associates degree in two years from the high school and the junior college, then move on as a junior to a four year university.
Get him a job at a legal office or some place technical, Radio Shack, Best Buy,
Here;s a thought, have him ask that girl in the corner to prom next year, you know the one, the bookworm who has no friends. IN high school one of the geek boys with a pimpley face, our valedictorian, never went to prom, I had to ask some sophomore I didn't really know. Had Chris asked me, I would have gone with him, but he was too scared to ask anyone. 10 years later he was an anesthesiologist for a very large hospital in Illinois, making a very nice paycheck. He's now head of the anesthesiology dept. At the U of Chicago he found his place Your nephew will too.