Thanks, everyone. He's in a specialized class with specialist teachers (which makes this even worse), leaving no alternative teacher options. We've found a far better school for next year, but need a way to survive the rest of this one.

I've been looking at the legal angle and there seem to be avenues I can threaten to pursue. I should probably accept that the teacher will only be stopped by an absolute writing prohibition and go that route.

I can't wait to escape this school!