This project requires bare copper and steel wire (alternatively, you can use a piece of a paper clip) and a lemon. The steel and copper wires serve as electrodes and are pushed into the lemon so that they are not touching. The acidic liquid in the lemon serves as an electrolyte, and the electrons from the electrolyte are collected on one of the electrodes. To use the battery, all you have to do is place something conductive so that it touches both electrodes. The power generated by a lemon is very small (about 7/10 of a volt), so you can safely test the battery by placing your tongue on the two electrodes.
This project uses about 1 foot of bare wire, which is bent into the shape of an obstacle course, which must be navigated with a wand. The aim of the game is to move the looped end of the wand down to the end of the obstacle course without setting off the buzzer. Connect a battery to a buzzer with insulated wire, leaving one long free section of wire and one short free section. Remove 2 inches of insulation from the longer side of the wire and then shape it into a loop. Tape the wire to a wooden stick so that the wire loop is at the top of it. Form the bare wire into an obstacle course and insert it through the loop of the wand before putting it into a non-conductive base. Connect the small, free insulated wire to the obstacle course to complete the project. If the wand comes into contact with the bare wire, the circuit is completed and the buzzer sounds.
This project demonstrates what happens when a circuit shorts. Set up a simple circuit with a battery, two pieces of bare wire and a bulb. Drop a piece of bare wire across the wires when the circuit is running, between the battery and the bulb. This causes the electricity to take the easier path, across the third length of wire, bypassing the bulb altogether.
This project involves a generator made primarily out of wood. The project consists of a small wooden box with a hole in the top and bottom, a wooden dowel, a magnet and insulated and bare wire. Place the magnet through the dowel. Put it into the hole in the wooden box so that it sits inside and can spin around. Put the top of the box on and then wrap the insulated wire around it. Expose the bare wire at both ends and then attach it to a light bulb. If the dowel is turned quickly enough, the light will illuminate.