I don't know about how things usually are because my kids aren't in HS yet, but I do know that their school district, during distance learning, has a blanket policy that parents are not allowed to record the teaching sessions. So I wouldn't be too surprised if voice recorders aren't allowed in many schools as well.
I'm no lawyer, but if I had to bet, I would assume that the wiretapping laws that would no doubt zealously be applied to such a recording event (if it ruffled the right feathers) wouldn't have an exception for that, as they were written before even speakerphones came into wide use.
