Clay:
2 cups baking soda
1 cup cornstarch
1 1/4 cup water
waxed paper

Cook over medium heat in a two-quart saucepan.  Stir until the mixture reaches the consistency of mashed potatoes.  Remove from heat and spread on waxed paper until cool.  Makes 2 cups.

Optional materials might include small trees, shrubs, or grass purchased from a hobby supply store, aquarium rock to outline mound shapes and or trails, etc.

Preparation of egg cartons - Cut tops off egg cartons at the hinge.  Cut down the center of the egg carton leaving two rows of six.  Turn the egg trays over to use for compound mound shapes.

1. Introduce the mound shapes by displaying everyday objects that share the same shape:
   • linear - hotdog
   • conical - mixing bowl upside down
   • compound - egg carton, necklace
   • effigy - cookie cutters
2. Check for understanding and see if students can think of any other everyday objects that share the mound shapes
3. Give each group a supply of clay and a piece of cardboard to use for a base.   Explain that they will be making a model of the four types of mounds in a natural setting.  Students will need to create a "scene" for the mounds by shaping the clay and placing it on the cardboard piece.  The mound should be labeled as to the type represented.
4. Allow the clay to harden overnight, and paint the following day.  Add trees, shrubs, grass, animals, etc. to create a scene from the Effigy Mounds National Monument.

Extension/Related Activities:

Do Match the Mound activity on Page 10 of the Junior Ranger Booklet available at the Visitor's Center.