A physics professor was very strict about attendance, and despised tardiness. Every student caught arriving to class late (especially those interrupting his lecture) was quickly reprimanded in front of the whole class. Students were quick to comment on the professor's genetics. Well, one day a student entered through the front doors of the lecture hall, while the prof was writing notes on the chalkboard. The professor caught the student out of the corner of his eye (this acute sense of peripheral vision, further supported the rumours of his evolution), and turned to face the student. He demanded, "What do you think you're doing?" Being a science student, one naturally thinks quickly, so the student snapped up and replied, "I came down from the back to get a better look at the board." The prof smiled.
Back in those days, it was required that in order for a student to receive credit for a particular course, a card (listing of his/her courses) had to be signed by the instructor/lecturer. It was, at the time, policy that students attend their courses. But depending on the size of the class, it was often quite possible to receive credit, even after not attending the class regularly. Not so, with this physics professor...if he didn't recognize you, you would have to repeat the course (& attend!). On one occasion, a student handed his card to be signed. The professor looked at the name, then at the student, and said, "I've never seen you in my class," and handed back the card. Now being a science student, he naturally thought quickly, and proceeded to the end of the line. When he was at the front again, he handed his card to the prof. The prof looked at the name, then at the student, and said, "You look familiar. OK," and signed the card.