A student in one of my scouting groups recently asked if the human body conducts electricity, to which I replied, "yes, it does." She then asked if I could show her how it does this. Well, not wanting to stick my hand in the nearby 115VAC outlet and show her firsthand how electricity conducts itself through the human body, i simply promised her that the next week the scouting group would meet, I would have something to demonstrate this. So I thought about this for a little bit and came up with a very simple circuit to demonstrate this property of human conduction. The circuit I simply named, "The Body Light."
The circuit's aim is to demonstrate that the human body is indeed a conductor of electricity and that by completing an electrical circuit by using the body itself as a "wire", can illuminate several bright light sources. The student will see firsthand the property of electrical conduction through the human body and also see that the resistance of a human body varies depending on how tightly the electrodes are handled as well as which parts of the body are touching the electrodes.
Next week when demonstrated, the kit proved to be quite successful. The students just loved the Body Light, as it was now called, and couldn't get enough of it. They connected themselves into large chains of individuals and could activate the circuit with 5 and more bodies connected hand in hand. Even the scouting instructors loved the kit and i was so surprised at how entertaining it was despite the fact it was electrically so simple.
This instructable outlines the design and construction of the Body Light. It is very simple and can be built in a very short time with minimal parts.
Video of the Body Light 1.0 in action: