It's probably a far stretch, but looks like the teacher handed over the boulder, and the autistic kid got stuck with the role of Piggy. While I can't comment on the mental disorder, I can comment on unnecessary traumatic school events.
I attended grades K, 1, and 2 at the school on Kadena AFB, in Okinawa. The bus I took home had many Japanese kids on it. And most of the time, I couldn't understand their native tongue. Apparently, I had sat in the 'wrong' place. I couldn't understand this little boy trying to tell me such, and then he wheeled his bookbag around and hammered me in the face with it. Imagine my further discontent when the bus driver storms into the back and yells at both of us what I can only assume are questions in bizzaro moonman language. And then getting off the bus, running to the folks in tears, only to see some angry lady dragging her demonic book-wielding child towards us in what I can only assume to be forced apology. My rage over this matter was settled years later, once I read about what we did to them with two gigantic bombs.
End point: kids are too young to fully understand the world around them, and the consequences of their actions. It's the role of the teacher to GENTLY introduce this concept until it's forcefully beaten into them around high school. If the teacher had a problem with the child in the class, she has a ring of academic professionals to take the matter up with, instead of turning it into Survivor.