Teacher recognition

What CS/Math professor or teacher most influenced your programming education? What lessons do still remember?

For me, it was my first CS class in the 10th grade at Memphis University School. The teacher was Tom Brown. He taught the basics like variables and loops and whatnot but in the process he also taught us how to think about programs - though we didn't call it Big O, we got a sense of scale of what goes on inside a program; how to think through an algorithm like a computer. He taught us to think about variables as values representing concepts and not just boxes. When I learned, much later about Knuth's ideas of literate programming it all seemed familiar. I've had good CS classes since, but that first experience in the 10th grade stands out.