Where the teachers looked, I don’t know.
With age, you realize that what was absolutely normal for you as a child, is now absolutely unacceptable for your children (from your point of view). We ran on the roofs and garages, drank from one glass, ate a sausage with a dog, bite in turn from one piece, someone's nose was constantly flowing soap, and going to play in a giant pit or on a dirty building-ship - was the most exciting adventure!
And now the children and the sludge do not flow, and there are no such sludges, and the buildings are all cultural, and it is strictly forbidden to drink them from one glass (I saw myself in school). We will disappear soon...