I traced an outline of a groundhog on black poster board, laminated it, and hid it on the playground while the children were out of the room. We all went outside; lined up on the sidewalk, and when I blew the whistle, everyone scrambled to see who could find the groundhog's shadow. Of course, the winner gets a marvelous treat. Make it more fun and hide more than one shadow!
The children in our program really enjoyed this activity. We taped paper on a wall and had the children take turns standing in front of a flashlight, while we traced each child's shadow on separate papers. The children loved guessing who was who when we displayed the final results.
I plan a week's worth of lessons on shadows at Groundhog's Day. One indoor activity that my preschoolers love is "Guess the Shadow." I drape three sides of an overhead projector with black bulletin board paper (so that the children cannot see what I am placing on the illuminated table.) After turning out the classroom lights, I place a common object from the classroom onto the illuminated table. The children have to guess what the item is from it's shadow. Once I have shown the children how the game works, I let each one of them take a turn selecting an object from a box of items I chose earlier. Things that make a distinct shadow are best: paint brush, scissors, crayon, magnifying glass, small cars, dishes/cups, piece of puzzle, toothbrush, glove, etc. This activity is easy to pull-off when you've planned an outdoor shadow activity and there is no sunshine!
Groundhog Tunnel Game... Have the children line up in a row. (If there are a lot of children, have them line up in two rows.) To form a tunnel, have them stand close together with their legs apart. Let the last person in the row be the groundhog. Have the first groundhog through the tunnel on his or her stomach. When the groundhog reaches the end of the tunnel, have him or her stand up and become a part of the tunnel while a new groundhog starts wiggling through.
Shadow Making... Explain to the children that objects that get in the way of the sun or a bright light cause shadows. Shine the light from a film projector, a slide projector or a lamp on a bare wall. Turn off the lights in the room. Let the children stand in front of the bright light and experiment with making their own shadows. Ask them to make big shadows, little shadows, animal shadows and moving shadows.
Last year my three year olds loved pretending to the groundhog as they took turns popping out of a medium sized cardboard box.