Well, and let's be specific. He is not being jailed by the government for speech crimes. He is being disciplined by his school for misbehavior. Yes, what you say can be deemed misbehavior. Even legally, you can be arrested for example for screaming in the middle of the night in a residential neighborhood, for example. It's not protected just because it is a result of air flowing over your vocal cords.

There really is a huge difference.