In US Labor law, a work stoppage by employees in the term of the existing contract is called a "Wildcat Strike". It carries criminal and civil punishments. Here's what a trusted legal source says about the actions.
The employer may, however, single out instigators for harsher discipline than is imposed against other participants.
Union stewards and officers may not be given harsher discipline than other wildcat strikers, unless:
The reality is that no one is taking the role of real management. Not the teachers, not the administrators, not the school boards, and certainly not the State Superintendent.
Essentially, it's now the challenge of the legislators to provide the maturity & taking control of a hissy fit. Will they encourage this lawlessness or condemn it?