The 6th-grade science teacher, Mrs. Parks, asked her class, “Which human body part increases to ten times its size when stimulated?”

No one answered until little Mary stood up and said, “You should not be asking sixth-graders a question like that! I’m going to tell my parents, and they will go and tell the principal, who will then fire you!”

Mrs. Parks ignored her and asked the question again, “Which body part increases to 10 times its size when stimulated?”