Coins, Squishy Circuits and SPARKs!
Bring STEM into your classroom with this activity and watch your students light up with excitement!
The following blog comes to us from Cynthia Sargent, STEM Professional Development Coordinator for Sutter County Office of Education in northern California.
Students at Marcum-Illinois Union School District in East Nicolaus, CA recently experienced two fun and easy-to-implement activities in their GATE after-school program to learn more about the basics of electricity. To encourage school-home communication and collaboration, each student took the materials home so they could impress their friends and family with their STEM skills!
In the first activity students built batteries from alternating layers of aluminum foil, dampened pieces of paper towel, and pennies. They stacked their cells 5 pennies high and used a SPARK Science Learning System and its included Voltage Probe to test the voltage of two types of batteries.
One stack of cells was constructed using distilled water to dampen the pieces of paper towel. The other type used salt water as the electrolyte within the coin stack. Measurements from the Voltage Sensor provided students evidence that salt water is a good electrolyte. Students could explore the activity further on their own, testing other electrolytes, adding more cells to the battery, using different types of coins, and so forth. It’s a great activity that can easily incorporate the science practices of NGSS.
Once the students observed the basics of a battery, they explored how to use a battery to create a circuit that lights an LED. But this wasn’t your standard ol’ circuit with wires. We made the circuits using homemade conductive play dough!
Conductive dough is made from flour, salt, water, cream of tartar and food coloring. Insulating dough can be made from flour, sugar and water.
As soon as the colored dough was passed out, the students were hooked. They lit up brighter than the LED when they successfully used the conductive dough to complete a circuit!
The “squishy circuits” activity (from the University of St. Thomas) makes it easy to understand the concept of a circuit, and to compare series and parallel circuits. The can measure voltage by placing the ends of a voltage sensor directly into the dough and explore the concept of resistance in the circuit.