Rodents had overrun a posh private school near New York City. The headmaster, a friend of mine, asked a health inspector to deliver a slide presentation to teachers and students, showing how to remedy the situation, such as properly storing trash and prohibiting food in classrooms.
The following day, a teacher had her very young students write a thank-you letter to the inspector. One student wrote:
"Dear Mr. Johnson,
Thank you for coming to my school. Until I saw you, I didn't know what a rat looked like."