Mr．Whitson taught sixth-grade science．On the first day of class，he gave us a lecture about a creature called the cattywampus，an animal that was wiped out(灭绝)during the Ice Age．He passed around a skull(头骨)as he talked．We all took notes and later had a test．

　　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 mistake！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 those things about cattywampus．There had never been any such animal．The information in our notes was wrong．Did we expect praise(表扬)for wrong answers？

　　We were very angry．What kind of test was that？And what kind of teacher？

　　We should have figured it out(弄……明白)，Mr．Whitson said．At the very moment he was passing around that cattywampus skull，hadn’t he been telling us that no trace(迹象)of the animal remained(存在)？He had described its color and other facts he couldn’t have known．He had given the animal a strange name，and we still hadn’t been suspicious(有疑心的)．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 notebooks are not never wrong．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 textbook was wrong．

　　I haven’t made any great scientific discoveries(科学发现)，but Mr．Whitson’s class gave me and my classmates something just as important：the courage(勇气)to look people in the eye and tell them they are wrong．He also showed us that you can have fun doing it．

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