Mr. Whitson taught sixth-grade science. On the first day of class, he gave us a lecture about an animal called the Cattywampus, an ill-adapted nocturnal（夜的） animal that was wiped out during the Ice Age, he passed around a skull as he talked. We all took notes and later had a quiz.

When he returned my paper, I was shocked. There was a big red "X" through each of my answers. I had failed. There had to be some mistakes! I had written down exactly what Mr. Whitson said.

Then I realized that everyone in the class had failed. What had happened? Very simple, Mr. Whitson explained. He had made up all that story about the Cattywampus. There had never been any such animal. The information in our notes was, therefore, incorrect. Did we expect credit for incorrect answers?

Needless to say, we were outraged. What kind of text was this? And what kind of teacher is?

We should have figured it out, Mr. Whitson said. After all, at the very moment he was passing around the Cattywampus skull (in truth, a cat's), hadn't he been telling us that no trace of the animal remained? He had described its amazing night vision, the color of its fur and any number of other facts he couldn't have known, he had given the animal a ridiculous name, and we still hadn't been suspicious. The zeroes on our papers would be recorded in his grade book, he said. And they were.

Mr. Whitson said he hoped we would learn something from this experience. Teachers and textbooks are not always right. In fact, no one is. He told us not to let our minds go to sleep, and to speak up if we ever thought he or the textbook was wrong.

Every class was an adventure with Mr. Whitson I can still remember some science periods almost from beginning to end. One day he told us that his Volkswagen was a living organism. It took us two full days to put together a refutation（反驳） he would accept. He didn't let us off the hook until we had proved not only that we knew what an organism was but also that we had the fortitude（刚毅，勇气） to stand up for the truth.

We carded our brand-new skepticism into all our classes. This caused problems for the other teachers, who weren't used to being challenged. Our history teacher would be lecturing about something, and then there would be clearings of the throat and someone would say "Cattywampus".

If I'm ever asked to propose a solution to the crisis in our schools, it will be Mr. Whitson. I haven't made any great scientific discoveries, but Mr. Whitson's class gave me and my classmates something just as important: the courage to look people in the eye and tell them they are wrong. He also showed us that you can have fun doing it.