Summary of 2011 Education Initiative:
CMMC, in partnership with the local Chatham Schools, is piloting its recently developed investigation modules in Global Telecommunications. CMMC was invited by the 8th grade technology teacher, Huntley Harrison, first in 2010 and more recently in January 2011, to pilot the Global Telecommunications activities in his engineering and technology class in the Chatham Middle School. The CMMC education team is planning further trials at all grade levels during 2011. For an example of the inquiry approach CMMC is using in the classroom, read on. . .
Example of "Waves" Investigations:
While students use cell phones and other wireless technology associated with radio waves, they have only a vague understanding of the science that makes wireless communication possible. To get a better of idea of how the students were thinking about wireless and how it works, Barbara Waters and Lee Anne Campbell, experienced science teachers, created a critical thinking activity for 8th grade students. The class was divided into teams of two. Each team was given a drawing with two cell phones and the students were asked to imagine that they were calling each other. Their task was to draw and describe on the paper their understanding of how the two phones connect with each other without wires. The resulting drawings demonstrated that the students were not clear about how the phones worked. These student ideas guided our subsequent demonstrations and discussions.
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Lee Anne Campbell introducing timeline.
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Lee and Barbara developed, with help from Chuck and other engineers, a series of investigations to help students visualize how the energy of water waves travels versus how the energy of waves of sound travel through air. Chuck also introduced the concept of frequency.
The next step was to help students discover how their cell phones communicate without wires using different sorts of waves (radio waves, for example), which travel in space, without air, at the speed of light-electromagnetic (EM) waves. To accomplish this, Chuck Bartlett, CMMC president and retired engineer, used a simple circuit with a bare wire at one end and a rough file at the other. (Similar to the spark gap Marconi first used to create a wireless message in Morse code.) About two feet away, Chuck set up a radio on an AM frequency producing low static.
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Chuck showing radio waves.
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He scrapped the bare wire along the file creating a sound students could hear on the AM radio. He moved the wire and the file in a two foot diameter circle around the radio, and the irregular static continued at the same volume. As he moved the file further away from the radio, the sound of the file diminished and finally was lost. At first students thought the circuit with the file was connected in some way to the radio, but once convinced there was no wired connection, the students began to describe their ideas about how radio waves travel.
At that point we showed a video that explained how radio waves were part of the electromagnetic spectrum along with light, microwaves, gamma waves, and many other types of waves, all traveling at the speed of light and at different frequencies. Many videos on the internet explain this; we used the following from NASA:
Introduction to the Electromagnetic Spectrum.
To conclude the CMMC telecommunications engineering module, Chuck drew the correct scientific way that cell phones communicate. The students watched intently because, by then, they really wanted to know the answer. The drawing was helpful to all of us, including the teachers.