Nature such as twigs and leaves
1. Take a nice long walk outside with the children. Collect twigs, leaves and whatever else they want to use to build their nest. They can collect it into their brown lunchbag.
3. Glue all the bits of nature onto the lunchbag.
Later they added some sunflower seeds to lure the birds into their nest, really though, it lured the squirrels and 'coons.