On paper I am leaning toward option #2 but honestly, I would want to know the teacher and the program, the structure of the program, and how they handled services before I really got behind it. It does sound like the best option all things being equal.
Will he have access to services such as speech and whatever else he needs there? Will services be integrated into the classroom setting? Pull out? Frequency of services? I would look CLOSELY at how that is handled. I may be biased but I feel our public school system handles support services better than anyone else around us, public, private, or charter, with certain notable exceptions. But that certainly isn't always the case and I agree that 32 kids is ridiculous and overwhelming.
So, a qualified vote for #2 over here from me.
I tend not to be a fan of the private school option for kiddos like your son, reason being that private schools won't provide special ed services and you'd end up taking him to the public school anyway. Typically private school teachers have less experience with and understanding of special education needs and strategies, less willing to cooperate (they can always ask kids to leave if they don't feel they are a good fit - a good private school usually has a wait list), and then time is taken out of school to travel to the public school for services. So for that reason alone I don't like option #3.
I have known several families in my city who have tried charter schools for their kids specifically because they had special ed needs, then ended up coming back to the public school system because they found we were more experienced and more able to accomodate the children than anything they found in a charter school. Charters vary a lot, though, and I know members on here have had great success with charters and special ed.
Really, and this is something I feel strongly about - a good teacher is a good teacher, and a bad teacher is a bad teacher. It doesn't matter what their philosophy is, or whether they are public or private - what matters is whether they know how to teach. And you will find a range of teaching ability anywhere you go. My friend here in town sends her girls to a fancy private school and even there she had a bad teacher for one of her daughters one year. The teacher is gone now, but she still taught that full year before the school managed to get rid of her.
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