I remember a bunch of things in science class in middle school, because I was really into science and it bothered me that they oversimplified everything to the point of being straight up false. Like a definition of "animals" being "something with eyes and a mouth". I mentioned several examples of animals without eyes, like corals, but the teacher just exasperatedly said that they did have small mouths. Ok, but your definition said eyes and a mouth, not or.
I also remember a question in a test about astronomy being "what is the biggest object". I thought about it for a moment and then wrote "the universe"; which I'll maintain to this day, was right. But it was marked wrong. The expected answer was the sun. I talked about it to the teacher, because it wasn't like I pulled the existence of objects bigger than the sun from my personal knowledge only, we'd explicitly talked about bigger stars and galaxies. But the teacher said "It was implied 'biggest object in the solar system' ". Implied how? It definitely wasn't written. I still want my point back.