There are many science fair topic ideas to choose from. Earth science is a great category because of its ability to demonstrate visual science principles. One easy project is an edible model of the Earth’s layers.
This science fair topic can be done using completely edible ingredients. Be careful to ensure that no one participating in the project has allergies to peanuts or any of the ingredients.
*Crunchy peanut butter
*10x confectioners’ sugar (also known as powdered sugar)
Chocolate graham crackers (regular ones will work if chocolate ones are not available)
*Milk Duds or other malted milk ball candies
Crush the graham crackers into a fine powder and set aside. Mix the crunchy peanut butter and confectioners’ sugar until it forms a stiff dough, much like Play-Doh. Roll the dough into a ball. Cut the ball in half and insert the malted milk ball in the center. Put the two halves back together and press firmly. Roll the reassembled balls in the crumbs.
As an alternative, you can melt chocolate chips over hot water and dip the completed balls in it before rolling in the cracker crumbs. Set aside in the refrigerator to allow the melted chocolate time to harden.
When the models are completed, you can discuss the following points:
1. Identify all of the natural or physical layers of the Earth.
2. What compromises the Moho and where would a geologist be likely to locate it?
3. Compare and contrast each of the following terms:
a. The Crust and the Lithosphere
b. The continental and the oceanic crust
c. The Mantle and the Athenosphere
d. The outer and the inner cores
4. Describe how it is possible for a solid to flow. Use an example taken from your model.
5. How would it be possible to test the physical state of each different layer inside of your model without having to cut it to look inside it?
6. How did Mohorovicic and other scientists studying the Earth
discover the nature and composition of the interior layers of the Earth?
7. How did your model taste?
If your science project topics are not the kind that allow discussion of your with patrons and visitors, prepare a presentation in the form of posters that can show what you are trying to convey to the public. Explain how each edible model was prepared and what layer was represented by what component. Perhaps you could even make enough edible models that you could cut them up into pieces you could offer to the public along with a handout explaining what each layer is.
If you take this route, remember to clearly label the ingredients used on the handouts so anyone who gets a piece won’t be unaware of ingredients that might trigger an allergic reaction.