Oh god. You just reminded me. I had a health teacher Mr.V, that was an army vet. Old, grizzly, but really kind. He kept a decommissioned grenade in the classroom, but didnt talk about it.

He saved the surprise for when kids fell asleep in class.

One of my poor, poor friends was one of those kids. Mr.V saw him asleep during a lecture, shows the awake portion of the class the decommissioned grenade, and tells them all its harmless, so dont freak out over what hes about to do. He grabbed the kid's hand and forces him to grab the grenade and starts YELLING to wake him up. Kid wakes up in a panic. Mr.V yells "DO NOT LET GO" and then pulls the pin.

He then proceeds to explain the kill radius for a grenade to everyone while this poor bastard is white as a sheet and sweating bullets while blubbering like an idiot. Mr.V takes the grenade back from him and simply says "There! You're up now!".

I guess making people confront their own mortality is a good way to teach health. I loved that man. He did not give a single fuck.