The final project in our three-part geology series, tailored for early elementary aged kids, is about metamorphic rocks. The focus of this experiment is to show “rocks” can change through heat, compression, and time. The “rocks” in this project are actually cookies. We made cookies, making some observations about the “minerals” (ingredients) we put into them.
Here’s what you’ll need: A cookie recipe (with some kind of ingredient, such as chocolate chips, raisins, and/or nuts, that will still be visible after the cookies are baked) and all the ingredients, cooking utensils, pots, and pans necessary to make your chosen cookies.
In my attempt to make the healthiest cookies possible that we’d enjoy eating, I decided to make Oatmeal/Quinoa/Chocolate Chip Cookies, adapted from the Oatmeal Raisin Cookie recipe I found in the cookbook, Quinoa 365, by Patricia Green and Carolyn Hemming.
Step 1: I discussed the meaning of the verb “to morph” with my son. He has a pretty firm grasp of the term “metamorphosis”, so he understood the concept that animals can change. We talked about how when something is morphed, it is transformed. This gave us a lead in to an understanding of how rocks, too, can change. How can something as hard as a rock be transformed? Heat, compression, and/or time.
Step 2: Get out the ingredients for the cookies. I explained to my son that each of these ingredients, for this activity, were going to be the “minerals” that rocks are made out of. When we cook together, he loves to touch and smell each ingredient, so this was a natural thing for him to do. He made observations about how each ingredient felt, looked, and smelled.
Step 3: Follow the recipe to mix the batter. As each ingredient is added, have your child make observations about what happens to the ingredient. For example, can he/she still see the cinnamon? Smell it? What happened to the butter?
Step 4: Now “compress” the cookies and place them on the baking sheet. Before putting the uncooked cookies in the oven, have your child again observe how they look. Moist? Round? Gooey?
Step 5: Bake cookies, remove from oven as directed, and allow to cool a bit. Again, have the child examine the now baked cookies (transformed by heat and time). Are they still moist and gooey?
Step 6: Give the child a cookie (metamorphic rock) to dissect. Have him/her break the cookie apart and ask them to look for the original ingredients. Can they find any? If using raising and nuts, yes. If using chocolate, have the chips taken a different shape? These “minerals” haven’t “morphed”. Discuss with your child that most of the other ingredients (eggs, butter, flour, sugar, etc) have morphed into something new.
Step 7: That’s it! Enjoy your cookies!
For our previous two kitchen geology experiments, check out:
- Rockin’ Experiment 1: A Lava-licious Igneous Meltdown
- Rockin’ Experiment 2: Make a Sedimentary Sandwich
Source: This science project was adapted from the “Metaphoric Munchies” activity in the book, Kindergarten Success, by Jill Frankel Hauser.