Six Times

Mr. Perkins, the biology instructor at a posh suburban girl's junior college, said during class, "Miss Smith, would you please name the organ of the human body, which under the appropriate conditions, expands to six times its normal size, and define the conditions."
Miss Smith gasped, then said, "Mr. Perkins, I don't think that is a proper question to ask me. I assure you my parents will hear of this!" With that she sat down red-faced.
Unperturbed, Mr. Perkins called on Miss Johnson and asked the same question.
Miss Johnson, with composure, replied, "The pupil of the eye, in dim light."
"Correct," said Mr. Perkins. "And now, Miss Smith, I have three things to say to you. One, you have not studied your lesson. Two, you have a dirty mind. And three, you will some day be faced with a dreadful disappointment."

Grey Matter

Q: Why do elephants do well in school?
A: Because they have a lot of grey matter!

Emotional Extremes

The aspiring psychiatrists were attending their first class on emotional extremes. "Just to establish some parameters," said the professor to the student from Arkansas, "What is the opposite of joy?" "Sadness," said the student. And the opposite of depression?" he asked of the young lady from Oklahoma. "Elation," said she. "And you sir," he said to the young man from Texas, "how about the opposite of woe?" The Texan replied, "Sir, I believe that would be giddy-up."