My uncle subbed at my school occasionally, not any class I was in. He had a beard. They wondered if he was a Communist.Facial hair was not allowed where I went.
He ruffled a LOT of feathers one day when he told kids in band class that they were "ignorant." One of them got upset, and said, "We're not stupid!"
"No, I didn't say you were stupid. What can you tell me about a (specific Air Force fighter Jet)? Nothing? I'm not surprised, as it was built decades before you were born. I used to fly one in Korea. But I don't know anything about playing the trumpet."
Kids went home and told their parents they were ignorant. Lots of parents got upset.