Hands On: Candy Rock Cycle

Big Idea
Rocks are constantly changing. Over a very long time, Earth recycles them into different forms using heat, pressure, and weathering.

Materials

• Starburst candies (3 different colors)
• Heat source (microwave or hairdryer)
• Heavy book
• Wax paper

What to Do

1. Sediment Creation
   • Take three different colors of soft candy (like Starburst).
   • Tear or cut them into tiny "sediment" crumbs.
2. The Sedimentary Squeeze
   • Pile the colorful crumbs into a stack.
   • Use the palm of your hand to press down as hard as you can for 30 seconds.
3. The Metamorphic Mash
   • Wrap your sedimentary candy in parchment paper or plastic wrap.
   • Use the heat from your hands to warm it, then twist and squish it firmly without melting it completely.
4. The Igneous Melt
   • Place your candy in a microwave-safe bowl and heat it for 15–20 seconds until it turns into a bubbling liquid.
   • Let it cool until it is hard again.

What You’ll Notice

• The sedimentary candy is stuck together, but you can still see the individual color bits.
• The metamorphic candy has wavy, blended lines and its shape has changed entirely.
• The igneous candy turned into one solid, uniform color and became smooth after it cooled.

What’s Really Happening (Parent Explanation)
In the Sedimentary stage, we simulate compaction. In nature, the weight of water and other layers presses sediments into rock. You can still see the original pieces because they haven't been chemically changed.

In the Metamorphic stage, we add heat and pressure. This doesn't melt the rock, but it makes it "plastic" enough to bend and recrystallize. This is how limestone turns into marble deep inside the Earth.
In the Igneous stage, the rock melts completely into magma. When it cools, it forms an entirely new crystal structure. This is how volcanic rocks are formed.

Key Takeaway for Learners

• Sedimentary rocks are made of pieces of other things stuck together.
• Metamorphic rocks are "changed" by being squished and warmed up.
• Igneous rocks come from hot, melted liquid that cools down.

Optional Discussion Questions

1. When we made the sedimentary candy, could you still see the original colors? Why?
2. What was the main difference between the metamorphic candy and the igneous candy?
3. Which part of this experiment felt like a volcano?

Why This Matters
This activity helps learners visualize the Rock Cycle as a continuous process rather than three separate "bins" of rocks. It demonstrates that the Earth is dynamic and that the very same materials are repurposed over millions of years through different physical processes.