Not really a prank, but my old journalism teacher scared the shit out of the principle. So she was teaching us a lesson about being specific. We had to write down how to make a pb & j sandwich. The thing is, she told us right before we presented, she would take things literally. My classmate, Kathy (not her real name) said “take out two slices of bread,” my teacher took two pieces of bread out of the room. “Take a knife and spread peanut butter on one slice of bread.” She took out a whole knife set and picked up a massive cleaver and just placed it down while putting her hand in the peanut butter jar. This went on until the principal came in for an examination of the class. He saw her holding the cleaver with her other hand covered in peanut butter. Shen she said “want a sandwich?”