hi, original mims bringer upper here. I just wanted to say, IANA teacher, but I was lucky enough to have one of those great, life changing type teachers for three years of high school physics. Its my understanding that he is actually very well known among other high school physics teachers around the state and even country. He was a stickler for teaching conceptually before quantitatively, and also for the proper use of words. He would do amazing verbal gymnastics to avoid misconceptions. A frustrating example would be when studying magnetism and you were not allowed to say things like "that marble just wants to sit there", he would point out that the marble doesn't "want" anything. Or the north pole of that magnet "likes" the south pole of that one.... the magnet doesn't "like" anything, and so on.
I had the pleasure of seeing him teach his advanced second year class 2 times, once as a student and once I was in the room working an independent study, which allowed me to observe it all over again. He taught a couple of months each year about electricity. We learned a lot by making and playing with the electrophorus made of a piece of hard insulation foam, a pie plate, a styrafoam cup, and a piece of wool. We made our own leyden jars out of film canisters, foil and paper clips.
There was something that he seemed to know instinctively, which I realized the second time I watched him teach the course. The water flow analogies will make a lot of sense to a few of the students. The rest will build misconceptions based on the idea that electricity flows like water (it doesn't).
I always understood the analogy pretty well, but some were confused. For example, if students were taught one behavior of electricity and how much it was "like water" then they would start to predict that other behaviors of electricity would be "like water". At some point the analogy breaks down and people are saying "but but but, that doesn't make sense".
I had been playing with electronics since I bought my first iron at 9 or 10 years old. This left me watching other kids in the class trying to learn the stuff I thought came naturally. I could understand water analogies, but most kids in the class would nod confusedly. It finally clicked with me that the ONLY reason I understood the water analogy was that my father was a landscape irrigation contractor, and a farmer. I had been around water flowing in pipes since I could walk. I used to build crap out of the fittings and scrap pipe.
What you have to realize is that the average high school student knows nothing about plumbing. They know that they turn the knob and water comes out. For previous generations this may have been different. If you grew up a farm kid "changing the water" in the fields like I did, then you might get it. If you were very mechanical and had worked on a radiator, you might get it. But most kids these days grow up playing with electronics instead. You would be much better off explaining water flows in terms of an electricity analogy than the other way around.
Keep in mind, that in most of the systems where you think of water flowing, it only flows because of gravity. Electricity flows for a fundamentally different reason. I believe the better way to teach electricity is by teaching a simple understanding of the Bohr model of the atom. If you can ask your students to bear with you for a few minutes, and explain that the Bohr model is a good but not perfect model of the atom, just as Newtonian mechanics is a good but not perfect model. Explain to them quickly, and non boringly electrons, protons, neutrons, and the forces involved. Explain valence electrons, conductors and insulators. Then start talking about a simple electrical circuit. Explain it in terms of a flow of electrons (do NOT teach hole flow!) from negative to positive.
The water analogy does have its place, I just think teachers need to be careful if they think "I will explain it in SIMPLE terms... like water in a pipe". The behavior of water in a pipe is something that is far more mysterious to the average high school student than you might imagine. Hydraulic pressure is a VERY complicated concept. In concept it can be more confusing than tiny particles bouncing from atom to atom. It just depends on how it is presented.
Hope this helps somebody. My high school physics experience was a magical thing. There are not nearly enough good teachers in the world such as the one that I had... and I suspect, such as the article poster. I sure do have fond memories of that class. That class was the only reason I got out of bed most mornings... There was not a lot of good in my life at the time, and I am pretty sure I would not have finished school without it. I truely may not have survived at all. In fact I make my living today as a licensed low voltage specialist electrician.
