If they are mid-ship and there are exits at both ends, then you teach them both exits and tell them "go in the opposite direction of the fire and get out". The last thing you want is for them to head towards your bedroom when the fire is on that end.
The point of meetup outside should be far enough away that they are protected from anything exploding, but close enough that they can easily see you, a police officer or fireman. And they should be taught not to leave the area with a stranger unless it's a police officer. They should not go off with a camp host, other camper, etc. unless you can give them those instructions yourself (or your wife).