Kids crafts should be easy and unfussy. The best kind of crafts are ones you could make with things you already have around the house. These masks are good for a rainy (waiting-for-a-hurricane) kind of day. These were made with some of Miles' friends last week for a Halloween get-together.
Cut a paper plate in half (use whatever size, but I used 8-inch ones which fit well on little faces). Cut a triangle at the bottom of the long end, in the middle where your nose is. I used a circle cutter to make perfect circles for the eyes. But you can just use an x-acto knife too. Staple a thin wooden stick to the paper plate; attach it on the back side of the plate. I used wooden coffee stirrers; they're thin enough to just staple to the plate. I painted the masks a few different colors. But you can leave them white and have kids decorate it themselves. Take out all your random scraps of paper, office labels, stickers, googly eyes, feathers, whatever you have lying around and let the kids get creative. The more imperfect, the better.