Just install recording software that records screen&audio on the computer., Otherwise setup wifi cam and record on sd card.
I’d guarantee that if a parent recorded the classroom sessions, and the parent posted the video or spilled the beans in public about salacious activity going on in the classroom, the Dems/Commies would try to charge the parent with a felony over eavesdropping laws in two-party consent states. It should be a non-starter as it’s a public school, but that wouldn’t stop the left-wing SOBs from trying.