I hate reposting, but this is too good to leave it up to Reddit's comments retention policy. Reproduced for posterity. But if you like it, do go to the link above and upvote...
"The guy on the left.
He was a graduate from the University of Zagreb or something and he had an awesome accent. And he was beanpole tall and twitched around. He was like a cross between Cosmo Kramer and The Count from Sesame Street.
He was incredibly passionate about what he tought. He would bang on the chalkboard, breaking the chalk, and say "DoyounderstandTHIS? DoyouGETthis?" and look at us all intense. And then he'd roll on with what he was going.
The dude fucking loved math. He was teaching ordinary diff EQ and you'd think he was Beethoven explaining crescendos. And he really didn't give a shit about homework. He'd sit there and drill us through stuff as if our life depended on us understanding. I saw that guy tear up a couple times. More than once, the professor next door would step in and ask him to keep it down. He spent maybe an hour explaining Euler's identity - and I shit you not, he got us to tear up, too.
We had one homework assignment. It was given about halfway through the class. We had a week to do it. And it took that entire week, in groups of two or three, five to six hours a day to do it. And we handed it in, and he didn't even grade it for like three more weeks.
When we got it back, there was a pallor over the class (what was left of it - a third of the class had dropped out). I had a 23%. I'm sure I turned gray. I went to see him - what the hell could I do? I mean, I needed to pass -
"DoNotWorryaboudit. AveragewaseighTEEEN. Yooodooverygooood."
When it came down to the final, it was one, simple, benign sheet of paper. It had one problem on it. There were absolutely no numbers on it other than (1). It started with "imagine a function..."
We had two hours. At 1:15, nobody had handed in a thing. I was just sitting there stunned, grinding through the first half. At 1:30, nobody had handed in a thing. At 1:45, he said
"Eeef...youtakezeetest choam wityou and feenishit, I veel passyou."
Nobody got up. We sat there and cranked through the fucking test. The survivors, anyway. We started with 30 people in the class. We finished with twelve.
I kept maybe five textbooks from college. One of them was Ordinary Differential Equations. It was an expensive book - too expensive for me to afford. The first time I went to see him, I apologized for not having the book.
He gave me his."