A classroom is a place where something is going to happen. And no matter how much the professor is prepared, no matter how receptive the student is, there’s no predicting what that’s going to be. And it always amazes me when a student will tell you years later, “I’ll never forget the day you said so-and-so.” You don’t remember saying that. But the student has remembered that and it has meant something to that person.
Most people don't remember most of what they were taught in college. But they remember those moments of enlightenment, of sympathy, and of transcendence.