Phwew! Makes me tired just thinking about your situation
Could you do something like this--gather a few laundry baskets, a few carpet squares--anything that is stackable and easily taken out and put back by your kiddos. Our first graders love to sit in laundry baskets. Carpet squares fit nicely under tables or in small open spaces.
One of our teachers also has a couple of those kdg nap maps that the kids love to stretch out on while they read. Don't give up--You can find simple ways that won't cause you a lot of effort!!