Our son is in a small special ed class, but it's at a regular elementary school. The class goes into the "mainstream" class for a few hours a day and they also have lunch and recesses, assemblies, etc. with the rest of the school.
He attended a general ed kinder class for a few weeks in October, in the mornings, to get a feel for his needs before we created his IEP. Once we had the planning meeting, they explained that while he responded well to the prompts given by the parasupport, he needed a LOT of prompts and about 3-4 sensory breaks over the span of 2 hours. They said there can be a risk of kids becoming dependent on prompts and the support aide in a setting like that. Luckily, they had the program available at a nearby school in the same district and we jumped on it.
I'm not sure what you mean by the kids not caring very much about each other...if they have similar disabilities, especially in the realm of perspective taking, that's going to be normal. My son complains about a couple boys in his class not being nice, but he does his share of trouble making back at them too. I see it as an opportunity to work these things out in real time, with qualified teachers and aides to assist. If he were in a gen ed setting right now, I don't think the kids would want to be around him much either.
I think our circumstance seems somewhere in between general and centralized, though. So this may not be helpful at all! Plus, I suspect that these programs are vastly different depending on where you are.
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40-something adult woman childhood diag. ADHD, suspect Asperger’s/ASD in place of or in addition to ADHD