Modeling Tectonic Plate Movement (or how sugary can it get?)

This week I was given the assignment of modeling an Earth movement with my students. Since I don't have a classroom right now I borrowed my friend's two sons and tossed in one of my own. They were a little reluctant to 'work' on a weekend but a little bribery and the promise of sugary snacks did the trick.


I decided to do an activity with tectonic plate movement. In the process, I learned a lot myself as to the specifics of what happens under the Earth, where different plates converge and how they shift. I had to do a lot of reading and certainly a LOT of writing for the portfolio write up of this inquiry. As usual, a week and a half of writing, editing, contemplating and planning took up the majority of my time. What looked like a simple lesson plan was actually a masterpiece (in my mind!) in the making. 


First, I had the boys tell what they knew on a sheet of paper, which they passed to the boy on the right until all 3 boys added their comments. This gave me an idea of what they knew and to what depth. Sean is older than Keegan, who wrote the second comment (*is struck with awe*). Keegan is a little self conscious of how much his brother knows and he does not, hence the comment. The third student, Chris, added a simple comment (convection currents) which is an important part of tectonic plate movement that Sean did not originally mention. 

This next paper was started by Keegan, who had nominal knowledge of tectonic plate movements. That was fine with me, and gave me an idea of what depth of knowledge  I would need to  teach him new concepts.

The next step was my engagement activity. (If I were to do this in a standard classroom, I would do this on one day and the next day I would have my students do the main inquiry with frosting and graham crackers). I had the boys take Snickers bars, crack the candy shell and manipulate the candy in different ways, modeling basic plate movements. They especially liked the divergent movement and made little mountains last out of their candy bars, which when done they proceeded to eat. 

After I had the boys watch a short video from National Geographic on tectonic plate movement along with a discussion, the boys were ready to use models to create plate shifts on their own. They modeled continental-oceanic collision, transform plate boundaries, divergent plate boundaries and continent to continent plate boundaries using vanilla frosting for the asthenosphere, chocolate frosting for the lithosphere, fruit leather for oceanic plates and graham crackers for continental plates. I let Keegan refer to  the sheets showing the different types of tectonic plate movements while I talked all of the boys through the task. 

Here's an example of an oceanic rift from a divergent plate boundary. The asthenosphere is almost showing under the thin layer of lithosphere:  

Here's an example of Continent to Continent collision. The boys realized that they were creating a small 'mountain range' without my prompting. 

To wrap up the lesson, I had the boys write a summary. I thought Sean did an outstanding job, so I will share his example:

If I were going to do this lesson over again, I would have done the candy bar inquiry on one day and the graham cracker/frosting tectonic plate modeling the next day. I think the boys were a bit overwhelmed by the end, then again they had had an awful lot of sugar in one sitting. 

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