I love models. Specifically dynamic, non-digital models. I love building something and then seeing it work. And apparently, lots of other people enjoy them, too. There’s something about seeing something work in real life (if still a model) rather than on a screen that drives home a process and helps people really understand what’s at work. Whether it be science, technology or engineering, models are necessary for designing better products, and understanding processes we can’t always observe directly.
Geology, in particular, is a science that requires models to study hard-to-observe processes. Geology may happen too slowly, over millions of years, or too quickly. The scale may be too big, or too small. Geologic processes can occur unexpectedly or they might just be too dangerous to get close to. Models help scientists study these processes, but they also help students and adults of all ages understand processes – and get them excited about learning, too.
Instead of writing specifically about the benefits of models in the context of science education, I wanted to share a few of my favorite geologic models that I have been able to develop over the years to get people excited about learning geology.
#3: Tectonic Forces
My current work at the National Museum of Natural History includes developing geology programming for a new education center that we will be opening this Fall, called Q?RIUS. (Can’t pronounce it? Just say “curious”.) When the website it up, I’ll be sure to let you know.
One experience in the works involves modeling how tectonic forces cause layers of rock to fold and fault through compression. Many universities do this in their geology courses, and post their videos online. In a museum setting, however, these models need to be developed so that even a 5th grader can operate it with minimal, or no supervision.
The model I have put together with the help of NMNH geologists and the exhibits department still needs some minor improvements, but most of the visitors who have tested the prototype have become really excited about tectonic forces. They have made strong connections between the model and the geologic structures they see in mountains and road cuts.
The model is a thin, rectangular cell, constructed of clear plexi-glass. The top is left open so that visitors can deposit layers of colored sand and flour. On one side are three rectangular bars that slide inwards, compressing the layers of flour and sand causing them to fold and fault.
My favorite visitor comment came from a girl in middle school who said it was fun and interesting to see something like this because diagrams and digital animations, like what they see in school, don’t feel real. Feedback like this affirms the importance of physical models as part of the learning experience.
The summer in which I was finishing my master’s thesis I signed up to teach a weeklong course in geological engineering to high school girls from around the country that came to visit Michigan Technological University. The program was called Women in Engineering, and fortunately I was granted the opportunity to lead this session despite not being a woman.
Each day for one week I would lead two two-hour-long sessions, repeating the same content, so by the end of the week the whole session went as well as it could have. Sessions were filled with multiple experiences, but the wrap up at the end was modeling a landslide, or a failed dam. In this demo I had to do quite a bit of prep work, but it was worth so much more than the effort. I was able to access the concrete lab, where I shoveled buckets of sand into a large sieves to isolate 2 grains sizes of sand. Dirt was collected from outside the building, along with some pebbles.
The geological engineering lab had a number of metal containers, about 60cm long, 20cm wide and 20cm deep into which we made dams and hills. At one end students layered the sand with thin layers of dirt and saturated them as they built up their structure. On the top they placed a thicker layer of dirt. To add some scale and context, we had them place Monopoly houses and hotels on the slope.
At the back of the dam or slope was space to allow us to pour water, which would begin seeping through the structure, over-saturating it. Now gravity would take over, and over the next five minutes we would slowly watch the top layer of dirt become wet and begin to slowly sag and slump. I would ask the girls to look for signs of impending disaster, but I’m pretty sure they were only waiting for their Monopoly house to fall over with the landslide.
#1: Volcanic Clouds
My first experience teaching was as a Peace Corps volunteer in Guatemala. I was in the environmental education program, and was also able to conduct my research for my master’s degree on Santiaguito, the local volcano. At first, my focus was on the volcano and working with the country’s geological and meteorological institution, INSIVUMEH. But I soon became excited about getting others excited about learning science.
Both of the schools I worked at were very small (one teacher) and were located on plantations that butted up right to the flanks of the volcano. I thought this provided an opportunity to teach something about a very personal subject. About every hour or so the volcano would have a small eruption, producing a small cloud of ash that would float away, so I asked my students why the ash cloud floated away and didn’t just fall to the ground.
Answer: buoyancy. To explain why, the classes made large cubes out of tissue paper which were lightly glued together. Each face was about 1.5m X 1.5m. At one corner of each cube we left an opening into which we injected hot air with a hair dryer. Despite the logistical difficulties of creating three large cubes in a tiny classroom, we were able to complete the project, and early one morning before it warmed up we went out onto the soccer field and began blowing hot air into the cubes.
Well, the first two cubes didn’t take flight, so I was understandably getting nervous. Fortunately the third and final cube was a success. Even before it lifted off, those holding it down could feel it beginning to pull upwards as we were filling it with hot air. After the countdown and release it began to lift slowly into the air and the younger kids began to trying to jump up and catch it.
Oh, and right after it took off, the volcano erupted.
Kids, adults, students of all ages, and lifelong learners can all benefit from using models. One thing to keep in mind when teaching with models, however, is that they are not perfect analogies, but certain aspects of them are relevant to understanding a physical process; a case in point is the volcano and the buoyancy of the hot air balloons. Nonetheless, just as important as helping us understanding science, models are very successful in getting people excited to learn science, whatever it might be.