Is it possible that your son was being distracted by the other kids?
My daughter has an arangement wher she is in classes for lab-work, lecture or group activities, but for written work or tests or quizzes, she goes to her couselor's office where she can work quietly without aggitation. Her grades shot up when this was figured out
Many kids with autism simply get overwhelmed by distractions.
He did well in small classes, not in traditional ones. He was easily distracted, but also defiant, and I believe he's passive aggressive as well.
He was one violent child, that's for sure. As a toddler, he'd go into a rage and run head first into the front door like a little bull. He figured out how to remove the safety covers off the electric outlets, and stick forks in them, blowing the breakers. He was 3, I believe. No matter what I did to childproof that house, he found a way around it.
He had no problem with attacking his older sisters, who are 5 and 7 years older than him. The teachers had to keep him off the playground because of all the fights.
Here's an illustration of some of the good stuff: when he was 12, he wrecked his remote contolled jeep. The battery pack looked like a miniature bundle of dynamite. Since this was almost Halloween, my older daughter and I thought he should go as the Unibomber for trick or treat. Hooded sweatshirt, dark glasses, and the battery pack.
The problem is that he strapped the battery pack to his leg, then told everyone at school that he had a bomb. The police were called, and he almost was arrested for a terrorist threat. The vice principal and I had a cordial relationship, so all he got was yet another suspension, and trash pick up after school.
There's more, but you get the idea. He wore me out. I still have no idea what's wrong with that boy...