Remember that I am more than twice your age. There weren't programs in the public schools, for gifted kids, when I was in second grade. Private schools were few and far between, so that wasn't an option either. There was one in this city, but far away from our home, and prohibitively expensive.
Rhys' IQ is 144, so well into the gifted range. Mine was 125.
There is no easy answer for him. He is unhappy where he is, and I think kids should be happy in school. If it means putting him back in the regular school, but pushing up a grade to accomodate his mind, I'm all for that.
I have a daughter in law with an IQ of 160, and her teachers thought she was retarded because she just didn't fit in. They actually put her in Special Ed, with the very slow kids. That's when her parents had her IQ done. She also was dyslexic. Things started happening at that school when they learned her IQ was that high. She is 25 now.
Anyway, all kinds of opinions out there. I tend to agree with advancing them at their intellectual level. I had kids in my school like that, and no one hassled them at all. But that was in the '50's too.