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Coin Weight Investigation

kids coin weight investigation activity materials

Do you know which U.S. coin weighs the most? Make predictions and explore different coin weights by creating your own coin balance scale. 

Grades: 2nd and up 

Materials: different types of coins, two paper or plastic cups, string (24 inches), scissors, ruler, clothes hanger, tape 

Time: 30 to 45 minutes

Steps:

  • Collect different types of coins.
  • Examine each coin and notice how they are different. Some coins are bigger in size, and some are smaller. Some coins are thicker than others, and some weigh more.
  • Make predictions about coin weights:
    • Which coin weighs the most?
    • Which coin weighs the least?
  • Build a balance scale to test out your predictions.
  • Poke two small holes in two cups. Make sure the holes are close to the rim and on opposite sides.
  • Cut two pieces of string that are the same length (around 12 inches each).
  • Tie the ends of the string through the holes in the cups to create two buckets.
  • Hang the buckets on separate ends of a clothes hanger.
  • Tape the string to the hanger keep it in place.
  • Hang the hanger on a door handle.
  • Using the different coins, test out their weights to see what coin weighs more. Check your predictions:
    • Are your predictions are correct?
    • What did you learn about the different coins?
  • Experiment with different coin combinations. Compare the weight of two pennies with one nickel, or the weight of five dimes to two quarters.
  • Use the Coin Specifications table to check your work.