Best school response will be to boot any protesters from school to protect themselves from such litigation, which they are likely to be found guilty when their professor employees likely urged the students to go protest, the school gave them facilities to plan protest, and so forth.
Yes, what you said, or have the students and their parents all sign some disclaimers that the school is not liable for any consequences related to the student participating in protests....
Kind of ironic - they brainwash their charges so well that if they try to "stop a protest before it gets dangerous", they would be sued for stepping on the little snots' 1st Amendment Rights - if they allow 'free expression" and the idiots get hurt, then they get sued for not stepping on their rights - I find it amusing.....