Rockin’ Experiment 2: Make a Sedimentary Sandwich

This the second in our three-part exploration of rocks.  I’m teaching my 5-year-old about the three kinds of rocks (igneous, sedimentary, and metamorphic), what they are made of, and how they are created.  All three science experiments are being conducted in the kitchen.  Today, we’re learning about sedimentary rocks.

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First, discuss with your child what sedimentary rock is made out of… mud, sand, and dead plants and animals.  Over time (hundreds of thousands of years), these materials are pressed together and hardened to create layers of rock.

Here’s what you’ll need:  Bread (two slices), peanut butter or Nutella (or, if allergic, honey, cream cheese, hummus, or another mud-like food your child will like), brown sugar, nuts or seeds (or, if allergic, an alternative hard food that looks like bone), banana slices or raisins, and a plate.

Process:

Step 1:  Spread the peanut butter (or other mud-like food product) on the slice of bread.  Mention that this represents mud.

Step 2:  Have your child sprinkle a bit of brown sugar over the “mud” layer.  The brown sugar represents sand.

Step 3:  Then have your child add a layer of “bones” on top of the mud and sand layers.  We used cashews, but use whatever works for your child.  These represent the bones of animals (which become fossils).

Step 4:  Next have your child sprinkle a some raisins or place some banana slices on top of the other layers.  These represent dead plants.

Step 5:  Lastly, place another slice of bread on top.  Have the child gently press down on top of the sandwich to simulate the pressure or compression of time.

Discuss:  Talk with your child again about the different materials that go into the making of sedimentary rock.  You can ask your child which layers they think are the oldest (the peanut butter, in this case), what’s the newest, and ask them why they think this is the case.

Source:  This science project was adapted from the “Sedimentary Sandwich” exercise in the book, Kindergarten Success, by Jill Frankel Hauser.  Love this book!!

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For our first Rockin’ Experiment in the series, see Rockin’ Experiment 1:  A Lava-licious Igneous Meltdown