We had one in University that I particularily disliked.
Before taking us into the Labs, they showed us a film of people with severe acid burns, medical stuff.
So once I got into the lab, I went to the 'dispensary', and asked for the obligatory "Rubber Gloves" that were needed for handling the acids, we were about to handle.
They 'shoooshed' me away, telling me that they didn't have any.
Well, this was all a (really stupid) 'practical joke', meant to 'teach' us an important lesson about acids.
We Handeled Nitric acid, (low power) so when we spilled it upon ourselves, which everyone does due to the nature of the glass bottles, it turns you skin yellow.
There after, while walking in the cooridors, you could tell the first year 'Chem' students, by their yellowed fingers, hands, arms, etc.
What I dislike about this, the loss is the message it sent to someone, like me, who did try to obtain gloves, heeded the warnings, and was still punished with "Yellow fingers" because they wanted to prove a point (to me) that I had already accepted, unfair/unjust to say the least!