Roll down a grassy hill with the children. Stand them up on the cut edge. Cut little flaps in one side and fold them back to represent the zippered opening of a tent. Allow children to decorate their tents with collage materials. Instead of grocery bags, you could simply use little brown lunchbags for miniature tents.
Children glue a cotton ball on the end of a real stick they collect from outdoors.
Have them place their cracker in the bottom of one of their aluminum pie pans. Then, we gather small sticks and tape the flames to the sticks and stack more sticks like you would to build a real campfire. The children and I then gather around the campfire to sing songs and tell stories. We even get into dramatic play by pretending to roast marshmallows on a stick. Here's a great idea from Christina Bell that could fit into so many different preschool themes.