So true! Fortunately for me, my early learning was a go-at-your-own-pace style, using workbooks. We had a bit of a kerfuffle when the teacher wanted to mark my answer wrong for 2 minus 3. I said it was -1. She said the answer was "it can't be done". I replied rather insistantly, "It can be done, and the answer is -1." We settled on agreeing that, "With what you've been taught so far in this class, this can't be done." :-) Hooray for teachers that treat their students with respect for their learning!!! Sounds like you finally got a good one in college, at least.