Potato Clock - Make a Potato Battery to Power an LED Clock

You may have the supplies for the potato clock lying around the house already. Otherwise, you can find the materials for a potato clock in any hardware store. There are also pre-made kits you can purchase that contain everything you need except the potatoes. You will need:

• 2 potatoes (or cut one potato in half)
• 2 short lengths of copper wire
• 2 galvanized nails (not all nails are galvanized or zinc-coated)
• 3 alligator clip wire units (alligator clips connected to each other with wire)
• 1 low-voltage LED clock (type that takes a 1-2 volt button battery)