So they listen for phone traffic, then what? Track down every user throughout the school day and intercept them? I would wager people who respond with IT solutions don't realize they at times sound like a 'tech bro' who believes they have s solution for everything even of they have no experience in education, no experience being an educator and understanding their contexts. It's no wonder why teachers in general in America are treated so poorly. Even folks who say they support teachers don't understand how much they have to do and with so many students and little time.