To make a potato battery, each group needs:

• 3 copper pennies (or copper strips), one per potato
• 3 zinc nails; these are galvanized nails, available at hardware stores
• 5 insulated wires, 15-20 cm (6-8 inches) long, with alligator clips at the ends
• 1 low-current, light emitting diode (LED) clock (or LCD clock) requiring ~1.5 volts (or a small LED)
• OR above materials can be purchased cumulatively in a kit, available online

• 3 potatoes (fresh)
• Make a Battery Worksheet, one per student

For the entire class to share or one per team:

• (optional) multimeter(s) or voltmeter(s); a multimeter measures current, voltage and resistance of a circuit; available at Radio Shack or other electronics stores or websites