Thanks for the great suggestions, guys!

Mosquito netting is the first thing that jumps out at me. The land they'll be using for this trip is almost swampy so the bugs are pretty thick in the summer. Mosquito netting will help keep their spirits up and the gsuge closer to the fun factor than the suck factor.

Wildman, we're going to avoid new wild edibles. They make me nervous as an adult and even more so for the kiddos on their own. There's bunches of mushrooms in this patch of woods, and I don't want them experimenting.

They each have their own survival kits, and have all the basics covered. I'm thinking of this kit more in terms of additional comforts for the group. Topo map, ground sheet and shovel/trowel are going in. I realy like the bow saw suggestion too. I'll be easier than just using their hands/feet/knives but safer than an ax shared amoung three kids with ADHD.

Les, you reminded me that DS and I made a few soup can hobo stoves this past winter. We both usually carry one but adding a bigger one to the group kit is a great idea. They'll be better off practicing their campfire skills than they will lighting an esbit tab with a bic. There will be lots of wood and as long as we don't get a binch of rain, they shouldn't have a hard time find finding standing dead wood that'll light. Maybe I'll throw in a pack of esbit pucks with it just in case.