The setting: Boston's Logan International Airport, the sidewalk by the road where you wait for airport shuttle buses.
The time: 9 a.m., during the Christmas holidays.
People: Mom, dad, son (aged 8), daughter (aged 10)
Mom impatiently awaits the Budget Rent-A-Car shuttle bus. Son stands behind her, chewing noisily on the gum he was given before the airplane's descent, to help keep his ears from getting uncomfortable.
Mom hears son squeal, "FIVE SECOND RULE!" and turns to see son PICKING UP A WAD OF GUM from the dirty, disgusting, trash-strewn sidewalk.
Mom tackles son, screaming, "NO!NO!NO!NO!!!"
Just in time.