Why math education is horribly wrong

Boy does this resonate with me. I found math interesting and was good at it until a particular freshman high school algebra class. The teacher was a substitute that ended up being permanent, and he had no interest in and very little knowledge of the subject.

That class killed my "math brain" dead. Math became the subject I hated the most, and that I did the worst in. I even came to think that I just had no mathematical ability.

The latter turned out not to be true, as I have since learned various higher-level mathematics without a problem (but on my own, not with instructors. I'm pretty sure I wouldn't be very successful with instructors and certainly not in a classroom situation), but that setback affected me for years and still does in several ways.

People often, and rightly, praise teachers who made a singular positive difference to them, but the opposite -- while rarely discussed -- happens too. Perhaps that's at least as common.