A school teacher had badly injured his back and had to wear a plaster cast around the upper part of his body. Luckily it fit under his shirt and was not noticeable at all. On the first day of term, still with the cast under his shirt, he found himself assigned to the toughest class in the school.
Walking confidently into the rowdy classroom, he opened the window as wide as possible and then busied himself with desk work, ignoring the chaos around him.
When a strong breeze made his tie flap around, he took the desk stapler and stapled the tie to his chest. Complete silence filled the classroom and he had no trouble with discipline that term.