Tell them upfront that if they get lost: "STAY PUT!!!!". Young people, (and some adults too), are mortally afraid of being ridiculed by their peers. So afraid in fact that they will blindly stumble about lost, hoping against hope that they will somehow find their way out. All the while of course they are only getting themselves deeper into trouble. Let them know that if they happen to get lost there will be no laughter once they are found, and make sure that everybody knows this rule will be enforced! <img src="/images/graemlins/mad.gif" alt="" />(stern face.)