One time the organizers, seeking to spice up the proceedings, had planned a mock-kidnapping. One of the kids (who was in on the joke) disappeared during the hike and soon enough we received something of a ransom note. Kids excited, kids crying. At the climax one of the organizers jumped out of the bushes with a nylon stocking over his head. The biggest and strongest kid in the group (who if memory serves me went on to become a bouncer at a local pub) hit him on the head with his flashlight, almost knocking the guy out. Good times indeed.
Of course nowadays the school would get sued into bankruptcy by angry parents for a stunt like that. :-)