Fun Science: Edible Rock Cycle

Do want to teach your kids about rock cycles? Want to try a fun experiment? Why not have a go at our edible rock cycle experiment, it is fun and easy to do and your kids can eat the results! Check out the post and try out this exciting experiment.

There are three different types of rocks: Sedimentary, Metamorphic and Igneous and it can be easy to get them confused. This experiment makes learning hands-on, visual and easy to remember.

For each different ‘rock’ you will need 1 square of aluminum foil, 1 square of wax paper and 3 starbursts (try and use colours that will stand out against each other). Other items that you will need and may require adult supervision include a toaster oven, towels and oven mitts.

  • First of all you need to unwrap your Starburst and  lay the foil flat on the table.
  • Sedimentary-Rocks-with-StarburstYou will then need to place the wax paper on top and stack the 3 starburst in the center of the papers.
  • The final step is to roll the papers over the Starburst tightly and form the foil around the starburst.


Sedimentary Rocks

Sedimentary rocks= pressure over time

This phase is simple, but it takes some muscle. You will need to explain to your children how sedimentary rocks are formed and you may wish to view the video below. Challenge them to change the shape of the three rocks (starburst) with their pressure alone. Try using your hands and feet to squash the sweets… you have now created a sedimentary rock!

Metamorphic Rocks


Metamorphic Rocks = Heat and Pressure

For this step, adult assistance is needed! After the children have wrapped up a new set of “rocks”, an adult can place them in the toaster oven. Leave them for a very short time… about 2 minutes. This will very depending on your toaster oven. Basically, the foil was warm to the touch and when I squeezed on the sides, it was malleable. You don’t want it to melt here, just get soft.

Carefully wrap the foil into a towel and let your children apply pressure. They will be amazed at how little pressure it takes to smash the rocks together.

Igneous Rocks

Igneous Rocks= Extreme Heat

Once again, you will need to wrap up the rocks.  You may want to Keep the same order of colors, so the observations are easier to make and describe.

For this step, you will need to handle the foil wrapped candy until it cools- adult supervision may be required.

Then place them in the toaster oven again on high heat for 5-10 minutes. You will need to frequently check on the ‘rocks’ to ensure that they do not burn! Keep it in the toaster until it melts into to a liquid. Once it had melted ,  removed it from the toaster and placed it on a towel for the children to observe.

Carefully opened up the foil and let them see what had happened, but you may not want your children to touch the ‘rock’ until it cools. You then need to pull away from the wax paper and observe.


Why not check out the 3 types of rock science song to help kids remember what they have learned!