The dean of Engineering once walked into a classroom and said, "Good morning."
The entire class chorused, "Good morning!"
"You're freshmen, aren't you?" he asked.
A bold student inquired how he knew.
"Well," he explained, "when I greet a class:
- Freshmen say 'Good morning' back.
- Sophomores quietly fold their papers and look at me.
- Juniors glance over the top of their papers, then return to reading.
- Seniors ignore the greeting and keep reading.
- Graduate students write it down."