God, I'm sorry you had such a situation in class - sounds very unpleasant. Props to you for being so honest! I don't know why teacher feel the need to ask such questions...
Speaking of teachers: In 10th class, we were asked by a teacher to write about our future life. You should have seen my face because I had no idea what I wanted for my future (expect going to university). At the time I was stuck in a relationship I actually did not want but it was very complicated. My thoughts were all about "After this ends, I do not want to enter another relationship, ever". Because I was afraid to face the truth back then and I wanted the stupid task to be over, I wrote something about going to university, owning a house, having my own library (because I love books so much), having two cats and a partner. But the moment I wrote down "partner" I did not think of a lover or someone I'm married to. It was more like "yeah, I'll move in with a friend". Back then I was friends with a girl I would have done it with and subconsciously, I've thought of her. I did not think it was strange at all, it felt very natural.
Other situation(s):
A boy made clear he "liked me" in 5th grade and I answered "You can't be serious" and walked away. That was very rude (especially because he apparently still liked me for several years after) but I couldn't handle his feelings and the situation, at all. It was horrible for me (took me years to realize WHY exactly).
I comforted a broken hearted classmate in 4th grade, who was rejected by her crush on a class trip, by saying something along the lines of the boy who rejected her is stupid anyway - my honest opinion of the guy. And if I remember correctly, I even wore a green rainjacket...hmm! (I still own a green rainjacket, lol).
I was taken by surprise (I was...14?) as Kim and Ron from the Disney Cartoon "Kim Possible" suddenly kissed and were a couple and I've always wondered if it was a mistake. Or why this needed to happen, why they couldn't remain close friends, etc. Their relationship actually started to feel a little more shallow after it and I've always wondered why I felt this way (liked the show as young teenager).
I was always more open to talk about sex than romance. Though sex seemed very strange for a long time, too (unless it was fictional).
The romance in Disney movies either went over my head or I just did not care for it. I liked Disney movies because of the songs, speaking animals, colors and settings but never for the romance.
A classmate once asked me if I would like to have children. I replied: "No". Then she asked me if I wanted to marry. I said "maybe" but wasn't fully satisfied with my own answer and wondered why once again.
Just a few situations I could think of right now, today I'm not surprised I'm writing in a forum for aromantic people .
Oh, and welcome @Ivan-The-AroAce to our community! It's nice to meet you! I hope you'll have a great time, we support each other as much as we can .