A friend suggests the easiest way to keep teens from loitering in mall food courts is to eliminate the food court’s free drink refills. While it wouldn’t be the only solution I think it would be a step in the right direction.
There’s also the “mosquito” method as well. It would need to be used where teens are and not kids, however, so that rules out a food court. Might be good for the open-air drug markets around town, though.