# Lesson Plan

## Coin Battery

Main Subject Area: Science

Duration of Lesson:  45 minutes

Keywords:

• Battery
• Current
• Dime
• Electricity
• Penny
• Voltage

Brief Description:

Students will explore basic principles of electricity and will create their own battery.

National Standard(s):

• Science as inquiry
• Physical science

Additional Subject Area Standard(s):

Objectives:

Students will explore basic principles of electricity.

Students will create their own battery.

Materials (online):

Materials (offline):

For each group you will need:

Copper wire

5 pennies

5 dimes

A mild soap to clean your coins

Salt water solution

4 paper napkins

Voltmeter (available at hardware stores, need just one for whole class)

Coins Used in Lesson:

Circulating U.S. pennies and dimes

Grade Level(s):   3-5     6-8

Procedures (online):

Procedures (offline):

Students can work in groups to create their own battery. They should record their steps and observations in their lab notebook.

1. To create the battery, students should first clean their coins with the soap.

Note- Remember, do not perform this experiment with any coins that you may be saving for a collection. Washing coins is not recommended for coins intended for a coin collection.

2. Next, soak the napkins in the saltwater solution.

3. Now have your students create a “sandwich” with the coins and the napkins. Fold the napkins until they are just a little big bigger than the coins. Alternating a penny, napkin, and then a dime, create a sandwich or stack. Make sure the ends of the stacks are different coins. Connect a voltmeter to the ends of the stack.

Why does this work? The saltwater solution is an electrolyte. It reacts with the metals, which are electrodes. Since there are two kinds of metals (in the two different coins) one metal reacts more strongly than the other, which leaves an electrical potential difference (voltage) between the two types of metals.

Assessment / Evaluation:

Students can be evaluated on the directions, observations and conclusions they wrote in their lab notebooks.

Differentiated Learning Options:

This experiment also works with solutions of lemon juice and vinegar. Students can test to find the best solution. They can also try this experiment with a penny and a nickel.