Inside a Geode

Inside a Geode lesson plan

Ready to peek inside an ordinary-looking rock? Your inside knowledge of gems and minerals becomes crystal clear with this sparkling geode project.

  • 1.

    Geodes are beautiful crystal formations. They are found in hollow spaces of mineral deposits that look like ordinary rocks on the outside. Over a long period of time, crystals form in these mineral bubbles, and the bubbles themselves become rock nodules from the outer mineral buildup. Many geodes are formed from quartz or calcite, although other materials such as amethyst crystals can also be found in geodes. Find lots of pictures of these beautiful natural formations. If possible look at them in a museum.

  • 2.

    To create your own geode replica, use Crayola® Model Magic® to create an outer stone nodule for your crystals. Form white Model Magic into a thick, bowl-shaped pinch pot. Use a Crayola Washable Marker cap to create a textured outer surface on your geode.

  • 3.

    Roll out a Model Magic snake. Use Crayola Scissors to cut the snake into several short sections. Cut a point onto one end of each section, making four small angled cuts. These are your crystals. Attach the blunt end of the pointed crystals to the inside of the geode. Fill the entire geode with these Model Magic crystals. Air-dry at least 24 hours.

  • 4.

    Cover a table with recycled newspaper. Use Crayola Washable Watercolors to paint the outside of your geode. Use a brush with stiff bristles to spatter a variety of colors on it.

  • 5.

    Paint the crystals inside the geode a light, pastel color by diluting the paint with water. Air-dry the geode.

  • 6.

    Use Crayola Glitter Glue to make your crystals glitter realistically! Air-dry before displaying your collection.

Benefits

  • Children research information about how geodes are formed and identify which minerals are crystallized within them.
  • Students study photographs or museum displays of geodes.
  • Children create a realistic 3-D model of a geode.

Adaptations

  • Research crystalline structure, and create a large model of a single crystal. Find out how to grow your own crystals.
  • Create two halves of a geode. Place them together to form a closed geode, like they are found in nature. Surprise a friend with this natural surprise package.
  • Where are geodes found in your area? From what minerals are they made? How many different crystal colors have been found?
  • Research information about quartz crystals. Where can you find them (hint: computers, fiber optics)? What shape are the crystals? Learn more about them from exhibits such as the one at the Crystal Sanctuary® at Mines Cristal Kébec in Bonsecours, Quebec, Canada.