Second Grade

Rocks and Clay in a Jar – Erosion Experiment

Question to Explore

How do ocean and rivers cause erosion?


  • small rocks
  • ball of clay
  • water
  • jar or Tupperware with a lid


I created this graphic organizer to record observations: Erosion Experiment

  1. Place small rocks and a ball of clay in a jar.
  2. Pour water into the jar so that it’s fully covering the clay and place the lid on the jar.
  3. Make a prediction. What will happen if you shake the jar?
  4. Draw what the jar looks like before shaking.
  5. Shake the jar for about a minute and draw/write what you notice.


Students noticed that the water became very murky as the rocks bumped against the clay. Students made the connection to the motion of the ocean and rivers. As the water hits the rocks, it leaves behind sediment, or little tiny pieces of rock. We concluded the experiment by watching a time lapse video of a cliff in Suffolk, UK. Over the span of one year, the cliff had eroded 17 meters!

Follow Up Questions

How does this experiment relate to what we see in everyday life?

How can cliff erosion be prevented?

Are there any examples you have seen in real life that have been built to prevent cliff erosion?


I created this graphic organizer for students to record their observations:

Erosion Experiment


This is where I got the lesson idea:


We watched this time lapse video to conclude our experiment: