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A Chip Off The Old Rock!

The rocks in the Earth's crust are constantly changing. Rock changes its shape and composition in a variety of ways. It requires energy to change from one type of rock to another. The rock cycle has many paths which can change the structure and type of rocks. In this activity, you will model the rock cycle!


  • Wax paper
  • 4 different colors of candy chips (use different flavors and colors, ex: vanilla, chocolate, mint and butterscotch)
  • Knife
  • Aluminum foil
  • Heavy books
  • Hot plate
  • Oven mitts
  • Rolling pin
Safety concerns: Be sure to keep all electrical, heat, and chemical safety rules. As with all science lab activities, the most important safety rule is to follow all teacher directions.


  1. Cover your work area with a sheet of wax paper.
  2. Place one type of chip on the wax paper.
    • Using a knife, carefully shave or break the chips into small pieces
    • Repeat this process until you have made shavings for all four types of chips.
    • Be sure to keep the shavings separated by color.
  3. Fold your aluminum foil in half.
  4. Open the foil and place one type of chip shavings on half of the sheet and cover the other half with a sheet of foil.
    • Use the rolling pin to press the shavings into a flat square.
    • Make an even layer.
    • Be careful not to tear through the foil.
  5. Continue pressing the different types of chips into different layers.
    • Do this by opening the foil and placing the second set of chip shavings on top of the first, the third layer on top of the second, and the fourth layer on top of the third.
    • Then repeat this process for the third and fourth layers.
    • Examine the layers and record your observations in your science journal.
  6. Fold the top half of the foil over the chip layers again.
  7. Place this foil package between two heavy books and apply light pressure for 2 seconds.
  8. Remove the foil package and carefully open it.
    • Examine the layers and record your observations in your science journal.
  9. Close the foil package again and again place it between the two heavy books.
    • Sit on the books for a minute or two.
  1. Remove the foil package from between the books and carefully open it.
    • Examine the layers and record your observations in your science journal.
  2. Carefully fold the edges of your foil to form an edge around the outside like a shallow bowl.
  3. Place the foil packet onto the hot plate. Be careful from this point on as you use the hot plate!
  4. Turn the hot plate onto medium heat (do not stir but allow the chip shavings to melt at their own speed.
  5. Turn off the hot plate.
  6. Using oven mitts, remove your foil packet.
  7. Allow your packet to cool in a safe place until the candy becomes solid again.
  8. Be careful not to mix your melted shavings as you move them.
    • Examine the layers and record your observations in your science journal.
    • Destroy all evidence of your rock cycle! (Clean up!)



  1. In your model of the rock cycle, what do the whole chips represent?
  2. What does the knife represent in your model?
  3. What do the chip shavings represent?
  4. What natural processes are responsible for disintegrating and decomposing rocks?
    • Where does the energy come from to do this process?
  5. When you pressed the chips into layers using the rolling pin what natural process did you model?
    • How is the energy for this natural process provided on Earth?
  6. What natural process from the rock cycle did the books represent?
  7. What natural process did you model when you sat on the books with the chips between them?
    • How does the Earth naturally have the energy for this process you modeled?
  8. What natural process did the hot plate model?
    • Where does the energy for this process come from on Earth?

Review Science safetey rules here.

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Teachers should view the Teacher Site Map to relate Sci-ber text and the USOE 8th grade science core.

Updated October 24, 2008 by: Glen Westbroek

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