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The “Ah-Ha” or “light-bulb” moment is one of the most rewarding in all of teaching. Sometimes those moments require a bit of work to make happen. A recent “Ah-Ha” moment occurred in my class as a direct result of my applying components of the engineering design process to student learning.

I had students compare the size of an acorn with the size of full grown oak tree. I asked students, “Where did the tree get all of the ‘stuff’ that makes up the full-grown tree?” Students then brain-stormed ideas and made lists of those ideas. As in years past, the student responses centered on nutrients and other things absorbed from the soil.

After the question and brain-storming session students researched the chemical composition of the ‘stuff’ that makes up a tree. Students identified the primary elements that make up a tree.  We then cycled back for a quick review of photosynthesis. Students were then asked to see if there was a connection between the equation for photosynthesis.

In group after group the realization that the carbon that makes up the bulk of a tree came from the atmosphere in the form of carbon dioxide. A true “light-bulb” moment for the students. Several students made a connection with the idea that trees serve as carbon sinks.