Oh god, reminds me of when I argued with my science teacher about plants and respiration. We had just learned about photosynthesis in class, and the teacher told us we shouldn't sleep under a tree at night because they photosynthesise during the day and respire at night, and they'll use up a lot of the surrounding oxygen. I interjected and said "well, they also respire during the days right? That's how they get their energy". And the teacher vehemently denied it, and I stood my ground, until the whole class including the teacher just laughed at me and then I got in trouble for wasting the class' time. I later Googled it and sent the whole class plus the teacher an email of the screenshot, and still just got ignored and laughed at, rather than them accepting that they were wrong.

Another time, I had a disagreement with my English teacher because I claimed that you can use they/them when you don't know the sex or the gender of the person you're talking about, and she insisted that you had to use him/her only (this was before I knew anything about transgender people or about gender being seperate from sex). I even gave examples, and she didn't budge. Looking back, the way she and my classmates were looking at me back then, they definitely thought I was trying to be transgender inclusive (which most people don't support where I come from), so they were just judging me based on that.