I suggest following the traditional Navajo practice - have them rise at dawn and run for a couple of miles, barefoot, in the snow.
Toughens them up....
LOL @ hikermor. thanks everyone! these are all great ideas. the kids are going to have a blast for sure! let's hope we can convert some of the parents so we can get them camping again! i can't imagine not wanting to camp with my kids but i'm in the minority in our group.