One of the best High School teachers I had, made a point of recording every class he taught. He hung microphones from the ceiling tiles, and told the students that this was ‘his’ class, and he was recording ‘his’ class.
“Why, you ask? Because when you parents come to me, because you aren’t paying attention - and claim that a certain topic wasn’t covered in class, I’m going to play that tape for them”.
We had a lot of goof-offs in our school, and I was one of them. Nobody, but nobody acted up in Mr. Campbells class.