Other comments have noted this but what you should do right now is document everything and shut up. If your son’s teacher is this upset, it might also be a good idea to get your son transferred to a different class, both to avoid additional confrontations and for educational reasons.

I personally think you should hold off on getting a lawyer until there is some indication that charges are actually going to be brought against your son. If you are able to get a basic consultation with a lawyer, that may be helpful, but I definitely wouldn’t spend more than that right now.

In terms of the process, there are three reasons why this will likely not be a big deal. First, people threaten lawsuits all the time and mostly don’t follow through. It’s quite likely the teacher never actually goes to the police/DA. Second, although your son likely broke the law, a prosecutor is very unlikely to bring charges against him. He is a kid, he didn’t actually harm or trick anyone, and the context doesn’t really align with the purpose of the statute, which is mostly about protecting clients, not opposing parties. Third, if he was charged and convicted, I’d imagine a judge would go very light on him as a result of the circumstances. This is total conjecture (if he actually is charged DO NOT base any decisions off of this opinion) but I can’t imagine anything tougher than a fine or possibly a small amount of community service.