Having been a camp counselor I'd say the most important thing you can do is keep it interesting for the kids. (Not an easy thing to do) Explain things to them while going on a hike, get them to go find things (pine cones, plants, leaves, etc.) to bring back to the group, have group chat about survival issues, etc. My best advice is to keep them active, engaged, and give them fun responsibilities. Group activities work well. Since attention spans at that age are almost nonexistent, try and give them things to do that they can immediately relate to. Let them make a bow drill, make a solar compass, whatever. The most important thing is to keep them engaged.