They never did it. Which I can understand because neither my elementary school nor my middle school had stopper covers over the pulls and I know at least a few times it was because some idiot pulled it for some reason. In my high school only the modular building didn’t have stopper covers over the pulls (all 3 of them) but I don’t think anybody ever pulled it. Since it was a Career and Technical High School which had a culinary program, we always joked that one of the students down there burned something.
They did try to tell me about drills before hand, but that only made me more anxious. I was worried about being in the bathroom if it went off because I mistook the remote strobes in my elementary school bathroom for horns. If I didn’t know, I was fine but I hated being out in the corridors by myself.