I liked to read and found (and understood) my farther’s calculus books while in elementary school ;) I was honestly bored in math classes through elementary and middle school. Teachers preferred to ignore me and especially my questions. I got through some math competitions with average success, then got invite to a qualification testing into a couple math high schools. Was selected in the last round of testing to the one I liked the most, and then graduated at the top of my year ;)

Edit: btw, I don’t know how I actually got these invites. Either from math competitions, or through my math teachers who found a way to get rid of me ;)