Using Annoying Noise to Control Teens

An inventor, Howard Stapleton, has developed a device "The Mosquito" used to annoy the young. Essentially it constantly produces an annoying chirping sound at high frequencies. It relies upon the fact that as we age, our hearing diminishes in the high ranges, therefore to adults the sound is imperceptible but annoys the young.

The device, called the Mosquito ("It's small and annoying," Mr. Stapleton said), emits a high-frequency pulsing sound that, he says, can be heard by most people younger than 20 and almost no one older than 30. The sound is designed to so irritate young people that after several minutes, they cannot stand it and go away.

While it is a creative solution to a difficult social problem, I doubt its use will become widespread. The social problem I refer to isn't loitering, it's not providing young people with safe environments to grow into adulthood.

What's the Buzz? Rowdy Teenagers Don't Want to Hear It - New York Times