Li'l Bastard Clock-Tampering Kit

The Li'l Bastard Clock-Tampering Kit is a device that causes clocks to go faster.

History
Bart used the kit to get the clocks at Springfield Elementary to go faster, thus shortening each school day by a few minutes. Eventually the tampering was noticed, and Mrs. Krabappel announced that to make up the time, everybody would have to stay for two extra hours.

Even though Bart wasn't discovered to be the clock tamperer, he took the announcement very hard because it was a beautiful day outside and he felt that it was too nice a day to be stuck in school.