But how SHOULD we teach kids about 'electricity'?
This is the one thing I lack, good replacements for the incorrect
material in K-6 textbooks. I'm not a teacher, so I lack the experience in
teaching children. I would need experience to create good curriculum
material. In the following, keep in mind that I'm an EE (electronics
designer) who complains about the accuracy of info in textbooks, but
without having the benefit of actually being an educator USING any of
these textbooks while teaching.
Note that the problem with electricity misconceptions is mostly in K-6
texts and children's books. In my experience it appears to be limited to
highschool grades and
earlier. For good and reliable information , textbooks at the
undergraduate college level are almost uniformly accurate. Unfortunately
they all base their explanations on mathematics, and would require
'translation' before children or the public could understand their
material. (And that's what my electricity website provides:
translating college-level physics textbooks into everyday
language/pictures/concepts which anyone can understand.)
I've only found one popular Electricity book which lacks nearly all the
Unfortunately it's out of print.
"Basic Electricity JE-101" by Gene McWhorter
It seems to be aimed at the middle high school level. It even
has quizzes at the end of chapters. Unfortunately Radio Shack replaced it
with "Basic Electronics", which lacks all the wonderful visual
representations of beginning electrical science found in the eariler book.
For a K-12 classroom textbook which is far above average, try Prentice
Hall's "Science Explorer" series, the volume on Electricity
and Magnetism by Dr. C. Wainwright of the excellent CASTLE project.
This one dates from 2007, and lacks the misconceptions I
discuss on this site. I don't know if other Prentice Hall editions lack
the errors, since Wainwright isn't the author, and few authors are aware
of the textbook misconceptions problem (or aware of their own.)
For high school level, an excellent commercial curriculum package is the CASTLE material. It takes a conceptual approach to electricity education, and is widely used in high school physics classes. It concentrates on charge flow and energy transfer concepts, and doesn't contain all the misleading "electricity" contradictions. Here's an online copy of the student manual. The required kit of parts is sold by Pasco.
My own attempt at some visual/conceptual introductory material is here: Explaining "electricity" with red/green plastic sheets.
If I were teaching, I'd concentrate on initially having the kids play with all sorts of real electrical devices. Batteries and bulbs, tiny motors, loudspeakers, maybe solar cells and LEDs (easily found at Radio Shack.) A secret: buy lots of "clip leads", wires with little alligator clips on each end. This lets you connect various devices together, even if the devices lack proper connecting terminals.
One particularly wonderful device is the "Genecon" hand-cranked generator,
available by mail order from Arbor Scientific among others.
It puts out about 8 volts DC max, and the polarity
will reverse depending on direction of cranking. Unfortunately it costs
over $50 each
or so. Maybe too expensive to have 30 of them for the entire class!
Look around and you can find
other types for less than
half the price.
At the very least, consider buying a single generator to play
Here's an electronics education secret: sometimes you can find digital voltmeters for well under $10 (even under $5 if on sale,) check out the multimeters at Harbor Freight Tools. Our city has a couple of those stores, so maybe yours does too (avoid mail-order shipping.)
Once the kids have had fun and maybe are starting to get excited about
the mysteries in the wires, only then start on the more standard
For explaining how charge-flow and electrical energy works, my favorite simple demo is two clothesline pulleys and a loop of rope (with rope ends butted together and duct-taped.) This "rope-ic circuit" shows how the electric charges in a metal can be forced to flow in a circle. Drive one pully into motion with your hand, and that pulley becomes a generator. The other pulley is driven by the flowing rope, and it behaves as a motor. To demonstrate an open circuit, have one person turn a pulley, and have another person grab the the rope at some point in the loop and hold it still. To illustrate an electric heater or electric light bulb, let the moving rope rub against your thumb so your thumb gets hot. Or, to illustrate Alternating Current, turn one wheel rapidly back and forth to demonstrate how AC circuits contain charges which sit in one place and wiggle back and forth, while energy is still communicated to all parts of the loop.
If you can afford to buy a bunch of $4.00 clothesline pulleys, perhaps you can even have the kids expand it into a vast network of wheels connected by a single loop of string, all of which will turn when a single wheel is turned, and all of which will stop when the "circuit is opened"; when the string is grabbed in one place. (I haven't tried this myself. Don't know how easy it is.) The cellulose molecules in the rope can represent the electrons in a wire. Flow of the rope represents charge flow in wires. The push/pull tensions in the loop of rope represent electric voltage. The slow speed of the rope matches the slow speed of charge flow. The rapid transmission of "horsepower" from pulley to pully represents the electric energy which moves at nearly the speed of light in circuits. To show that electrons aren't so invisible, replace the loop of string with a loop of fishline. When you turn the pulleys, the fishline appears not to move (since it's very smooth.) Similary in wires, the charges are visible as a silvery metallic color (all metals have this), but when the charges all begin to flow along, we cannot see the silvery stuff start moving (since it is far too smooth, it has no marks which might show that it's flowing!)
Another similar "visible electricity" demo would be a circle of railroad track and a bunch of freight cars as the "electrons" (With no engine of course). Include enough freight cars so that you cover the entire circle of track. Then push one freight car along, and you transmit kinetic energy almost instantly to all the cars in the loop. The cars represent the copper's electrons which flow within a wire. Or, put a row of marbles in a circle on top of a large steel coffee can. If you can get hold of a bag of old golf balls, maybe you can fill a circle of model railroad track with large rolling "electrons" (N-gauge track might be needed, I don't know if golf balls will hit bottom on the standard HO-gauge track). Fill the entire track with balls, so when you push one ball, all balls must roll at the same time like a big flywheel.
My usual suggestion is to abandon the terms "electricity," "current," and "power," and instead start out with as much correct terminology as you think is appropriate for that age level.
I've learned an important lesson from the "new math" debacle in the late 1960's. I don't want to become one of those experts who causes similar problems. As an educator, I have too much theory in my head and not enough teaching experience. If I were to write a K-6 science book, that book might appeal more to academics and engineers than to children and educators. Curriculum material should be created by teachers, not by content experts having only months of classroom experience.
If anyone should figure out more good techniques, lesson plans, activities, etc., then by all means get them onto the WWW so other educators can benefit. We can point our "Electricity" websites at each other.