We had to watch all sorts of terrible stuff at school. I always wondered whether it really taught us anything. Some stuff is just not suitable for teenagers.
I remember a film about motorbike accidents. A stuntman had lost control over his bike in a burning tunnel made of straw. He walked out of that tunnel, burning all over, screaming in a most horrible way and then died. Not sure what that part was supposed to teach us. Normal people don't drive through tunnels of fire.
Then we watched a film about child birth, with all the details and the camera right on the baby's head when it came out. It's quite natural, but still made most of us sick at that age.
And we had to watch several films with footage from concentration camps. People getting killed, their skinny bodies being pushed into mass graves by snow plows, bowls full of chopped off heads, etc.. Maybe you need to see things to believe them, but at that age it was just too much for us.