Please excuse my ignorance, but what is an "electric-powered squirrel cage?"'

I'd also add some simple forms of entertainment to keep busy. A few decks of cards, some simple board games/jigsaw puzzles and coloring books w/crayons will keep kids and adults busy and reduce tension. I just remember being snowed in with the family when growing up and that entertainment kept us sane during the 2-3 days being cooped up.

Some comfort foods might go a long way to improving morale. I'd store several boxes of favorite cookies/snacks/candy along with the usual freeze-dried rations.

Best of Luck to you! Sounds like a great idea...