K.P.
I would schedule an appointment with the teacher, principal and school psychologist within the next week. There could be a lot of things going on, but you need to find out why he is engaging in these behaviors and what reaction from the teacher is reinforcing the behavior.
It could be a learning difficulty (work avoidance), it could be an issue with a child or the teacher (removed from the situation), it could be an emotional issue (avoid add'l stress)... lots of different reasons, but point being you need to find out why he's behaving this way.
If you don't know the "why", you will just be guessing when it comes to solutions!