It sounds like his current situation is not good either? I don't see that signing him up for the same boredom and adding in even more restrictive/punitive bahavioural expectations is a great idea. But single year accelerationis pretty simple compared to 2+ years. If he was only 12 months ahead in third grade that could be dealt with just by choosing a school carefully.
Either way, he'll be bored, but with a year extra age maybe he'll have better self control and be able to cope with afterschooling. Either way, it sounds like they won't be teachinghim anything, whether he goes this year or next?
In general, I favour play based preschool (because everyone can have fun then, and they can work on social skills), kindergarten entry on time (not early, because they're not going to teach them anything anyway), and skipping 1st rather than K (because K has more play, more socials skills work, and less time at desks).
But the school will hate you if you redshirt him and then skip 1st.
Dude, I see that claim that kids with high IQ are super mature made all over the place, but have seen slim evidence of it IRL. They're kids who like fart jokes and wriggle and hit their friends just like any other, even if they have conversations about esoteric subjects (which display a very age-appropriate lack of wisdom).
