I do not miss one thing about school

MAYBE the teacher had been getting more and more unsure of themself as they walked around realizing everyone else was doing it wrong, until they got to you who had read it correctly and gotten the right answer, using the correct method. So they now knew their exam was written fine but the others had made wrong assumptions instead of reading carefully.

I did say maybe.

one of the few perks a teacher has:
messing with kids’ minds

and this one is good for ’em

Lol, once had a teacher look over my shoulder at my exam and sit down and try to help me. Then the following lecture have him declare to the class that he was frustrated that “one student” couldn’t even yada yada.