In a high school sex-ed class, the topic was birth control. The teacher discussed all the usual methods and devices— condoms diaphragms, sponges, patches, rings, caps, IUDs, and of course, the Pill.
"However," said the teacher, "you should bear in mind that these methods can have their side effects, especially the Pill."
A girl in the back of the room vigorously raised her hand, and when called on, said, "I know a birth control pill with no side effects! "
The teacher looked surprised. "What pill?"
"Aspirin."
"Aspirin? I never heard of such a thing," said the teacher.
"But it really works," said the student. "The girl holds the aspirin firmly between her knees."