I had some good HS teachers and some mediocre ones, I don't recall any really bad ones. The good ones held my feet to the fire.
My basketball coach taught American history which we were supposed to take our junior year, but I had a conflict and took it as a senior (which was nice because I had a slight chance of impressing some junior girls in the class). He was a solid teacher, took it seriously, which of course many coaches did not. My last day in class I wore a bright orange wig, very out of character, and sat in his class, and he came in and scanned the room as he always did and just barely hesitated when he saw me, and then after a minute said "I'd like to welcome our new student to class."
He was a good man, went by the name "A. Z.", he was always called that in the papers etc. One day we snuck into the coaches off to check his DL, he name was Aubrey Zelma. We of course called him "coach". We had a good team my senior year but lost too many close games and did poorly when our MVP was injured.