Four high school boys afflicted with spring fever skipped morning classes. After lunch they reported to the teacher that they had a flat tire.
Much to their relief she smiled and said, "Well, you missed a test today so take seats apart from one another and take out a piece of paper."
Still smiling, she waited for them to sit down. Then she said: "First Question: Which tire was flat?"
source: http://www.jokesabout.net