Wednesday, July 14, 2010

Ohm's Law is just a theory.

It was a science lab in junior high school. We were studying electricity and magnetism. The assignment was to hook up various circuits involving a battery, some resistors, and a meter. We were to record the readings from the meter and verify that E = IR. This should be easy; I had already built a Ham Radio from a Heath Kit and I even knew how to solder.

This was not a good day. My data did not seem to agree with Mr. Ohm's theory at all. Of course, if it said so in the textbook, it must be true. Perhaps I was doing the calculations wrong? Possibly I was reading the wrong scale on the meter? Or, more likely, was I reading the color codes on the resistors incorrectly? Still, no matter how many times I double-checked my work and re-tried the experiment, E did not turn out to be anywhere close to I times R. I came back and tried again during lunch. I came back after school.  Eventually, I ran out of time and turned in my troubling results. Everyone else seemed to have gotten the right answers during class. I was devastated. In those days, I had thought I would become a physicist; but I began to rethink my career options that evening.

The next day in science class, a tough lesson unfolded for all. The actual wires we had been issued for our Ohm's Law experiments were not the typical hookup wire they appeared to be, the sort one might use for this sort of thing. Our science teacher had played a devious trick on us. He had substituted special, high resistance wires. My data was right! At first I felt angry. Apparently, other students may have "fudged" their data so as to obtain results consistent with the textbook expectations. It was a lesson no one in our class could ever forget, a science teacher's rendition of "the truth shall set you free." My posting about The Science Fair and The Troubleshooting Game, written more than a few decades after that day in science lab, was, without a doubt, a direct consequence of my junior high science teacher and his trick wires.

Instead of a lab, my teacher could have lectured to us about the importance of reporting the data from our experiments carefully and accurately. He could have cited examples of infamous scientists in history who had lost credibility and ruined their careers, when their reported findings could not be replicated and colleagues began to suspect the integrity of their data. We could have taken a multiple choice test about the scientific method and answered questions about simple circuits by solving with Ohm's formula. Instead, he had designed a hands-on learning activity that created a vivid memory, changing forever how his students saw the world. When will we devise assessments that capture this kind of impact?

Current technology provides unprecedented opportunities to design innovative learning activities that build on our students' natural curiosity and wonder, activities that inspire and encourage, activities that demonstrate deep principles and powerful ideas. Unfortunately, technology is so often used, instead, to enable "delivery of information" to become more efficient and slightly more compelling. Providing "training" to teachers on (say) how to do presentations using an interactive white board may lead to improved "delivery." However, the benefit of new technology is severely limited without also radically changing this outworn pedagogical approach. Professional development must go beyond "learning how to operate the device" and instead challenge educators to take on a completely different role: instead of being the "givers of knowledge," great teachers should use technology to create learning experiences that foster a deeper kind of understanding, an internalization and "ownership" of the knowledge that will not be forgotten a few days after passing the test. Our goal for technology integration should be to design learning experiences that change, not just test scores, but lives.

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