Sedimentary Rock Snacks

Using rice krispies, marshmallows, chocolate chips, and candies, students create layered snack bars that model the formation of sedimentary rocks in the rock cycle.

1. Grease an 8×8 inch baking pan.
2. In a microwave-safe bowl, heat marshmallows and butter for 1–2 minutes, then stir until smooth.
3. Mix in rice krispies cereal gradually until well coated.
4. Press half of the mixture into the bottom of the greased pan.
5. Add a layer of chocolate chips on top.
6. Cover with the remaining rice krispies mixture and press lightly.
7. Sprinkle mini M&M’s on top and press gently so they stick.
8. Allow the mixture to cool for about an hour, then cut into bars.

How to Make Sedimentary Rocks - Rainy Day Mum:

Making Edible Rocks - Pinal Geology and Mineral Museum:

📄 Edible Rocks For Kids - Sarah McClelland: https://littlebinsforlittlehands.com/rock-cycle-for-kids/

• Use different candy pieces to represent various sediments.
• Add crushed cookies or pretzels for additional “rock fragments.”
• Create a three-layer version to show more complex sedimentary layering.

• Supervise children when using the microwave or handling hot marshmallow mixture.
• Allow the mixture to cool before eating.
• Be mindful of food allergies to chocolate, marshmallows, or candy ingredients.

• How does this snack model show the way sedimentary rocks are formed? (The different candy pieces represent sediments that are pressed together in layers.)
• What real-world processes are missing from this edible version of the rock cycle? (Long time scales, pressure, cementing minerals, and natural erosion.)
• How would metamorphic or igneous rocks be represented in a food-based model? (Metamorphic could be made by reheating and pressing ingredients, igneous by fully melting and letting them solidify again.)