In a somewhat reverse scenario, when I was in 4th grade (9 years old), I knew 100% that I was getting nearsighted, and I absolutely did NOT want glasses. Fortunately (debatable) we got to pick our seats so I always picked a seat in the very first row, where I could kinda-sorta-almost see what was written on the board if I squinted. And I was also way above my grade level so I was able to fake it pretty well for most of the year even when this started to fail me. My mom insisted on taking me to get my eyes checked about 2/3 of the way through the year and I couldn't fake my way through that, though, so I finally got glasses, but by that point I was used to sitting at the front of the room, so I choose front-of-room seats when possible for most of the rest of my schooling. There's probably some moral here but I don't know what it is.
I moved states and schools midway through 3rd grade and was seated alphabetically, in the back, for the first time in my life. The teachers in my previous school knew me to be a model student, so would sit me up front "to set an example."
My parents couldn't figure out for the life of them why I was suddenly struggling and thought I was having adjustment issues. I had taught myself to read when I was 3; how could I suddenly be having trouble keeping up?
It took longer to figure out because I was only nearsighted in one eye. I was tall for my grade, so as long as the person in front of me to the left was shorter than me or the teacher was writing high enough on the board, I was fine, because my left eye was fine. But when everything aligned just wrong, I was suddenly helpless, because my right eye could barely see clearly an arm's length from my face! It's a hard thing to notice when only one of your eyes isn't working very well, especially when you're 9.