These are not really crafts, but fun anyway.
SNOW- When it's too cold to go out in the snow, I bring it in. I take a bucket out scoop it full of the cleanest snow I can find and put it in the middle of the kid's table. They have spoons, cups, bowls, etc. and they love it.
SOAP - I had the same group (5 toddlers and a 3yo) one year and when painting was over, I would pull out the Ivory soap bars (not toxic) they each get one, a dish of warm water and a sponge. Clean up is easy too, it's soap! To add to your fun, gather up the toys and have the kids do the washing for you.