My wife's best friend is a second grade school teacher. In a few weeks she is going to have me in to discuss electricty. It is part of the curiculum and I guess it makes it more interesting to have someone "special" come in.

We are supposed to do a circuit, so I was thinking maybe of a potato circuit, but I'll have to google it, I have never done one, just heard about them. But I was also hoping to come up with a demonstrtion that had a little bit of a wow factor. My brother has an HID lamp testor thats pretty cool, basiclly it will make an FO32 kind of glow while you hold it in your hand. Also, I recently discovered that if I shuffle my feet on carpet to get a good static charge with FO32 in hand, and then discharge by touching the end of lamp to ground, I get a little flash. In a dark room that might me neat.

Any ideas? Something a little safer than a Jacob's ladder?

You might want to be carefull with children and the example of holding lights and making them glow or flash. Might send the wrong electrical safety message. Don't get me wrong, its neat! (get 2 kids to shuffle their feet while holding each end - might get it to light - don't know if it would work... Then again I imagine kids skipping around the room in the dark with a fragile glass rod, Hmmm. )

I remember being a little kid and seeing a magician hold a A-19 in his hand and light it. I was facinated! I have no idea how many dangerous things I tried to try to replicate it. I still have no idea how it was done!

Anyway the potato or lemon battery is cool... http://195.92.138.215/pdf/inter_learn/experiment_2.pdf

Check this out
http://www.teach-nology.com/teachers/lesson_plans/science/physics/electricity/

Make sure you practice whatever demonstration you are going to do. I've tried the lemon circuit before with my son and I never got it to work. Not sure if I had the right stuff or maybe I wired it wrong Either way, make sure it works before going in.

What about the old 1.5vdc "dry cell" batteries that were about 2" x 6" tall w/screw terms on top?

I remember those from "science projects" as a youngster... let 'em hook a light bulb and wires up with a switch.

Dougs got it. My second grader saw that idea in a book and off to Lowes we went. They have a whole bunch of stuff for science projects like mini lampholders and lamps and switches. He made a circuit and brought it to school and the kids loved it.

I've done this before, and it was in line with a conductor/insulator lesson. I got a battery type, aligator clip and probe type continuity tester, and explained the circuit with the battery and light (have a 2nd tester or your toast if the first one dies). Then I showed that a coin, for instance is a conductor...and a pencil isn't. I let them guess if things were conductors or insulators, then let them test it. The light going on or not was a big winner. Of course they got a big dose of safety first about not plugging things in and how dangerous electricity is.

Dave

Great suggestion Dave. I wish I did that. I did a 5K bring your dad for show and tell a long time ago. They liked the big and little comparisons. Like a 1000W metal halide and the Mini-Mag lamp, a 4" and 1/2" connector, 500kcmil and # 14, or large and small lugs or fuses. I packed my tool pouch full of tools and let all the kids lift it. Blaming my son for the rubber chicken in the bag cracked them up.

hey guys,

Great suggestions, really. All of them. I think the battery with the bulb is the way to go. safe & simple. Heck, even at my age I still enjoy the first throw of the switch on a circuit I've built.

I was a little sketchy on the static with the lamp idea. My wife wondered if it was a good idea too. Maybe I should save that one for a different crowd.

See if you can find one of the knife style switches... always great for dramatic effect!

http://www.esfi.org/esfilib/maykit-dl2005.php

How about the electric motor made from paper clips, wire and a battery. I always liked that one.

Just a couple of additional thoughts - the site www.howstuffworks.com has some easy-to-understand explanations that might be a model to use when sharing complicated concepts to youngsters. Also, don't forget to emphasize the safety issues to them, as one who 'tinkered' with tools whenever the chance arose I can tell you I had a few narrow scrapes with destiny and my guardian angel had to step up the pace quite a bit!

I don't know about where you are, but our local utility has a lot of fun educational safety material for kids, like comic books etc. Maybe you could get something like that to hand out.