Teaching science and playing with food seem like an unlikely pairing. However, using food to illustrate and explain geology is a fantastic (and tasty) way to introduce concepts. Using food, abstract theories can be presented in a way that helps learners visualize some of Earth's geological events. Hands-on exploration, manipulatives, and visual aids can make learning geology memorable.
To put it simply, plate tectonics are a theory that explains the large-scale motions of the outer most layer of the earth: the lithosphere. The lithosphere is moving and shifting constantly due to the heat inside the earth. When they bump into one another, it causes interesting things to happen at the plate boundary.
Your class can create the different types of boundaries using a number of food items. My favorite healthy option is using hummus and crackers. Have pupils place a thick layer of hummus between crackers. The top represents the plates of the lithosphere, the gooey middle is the asthenosphere, while the bottom cracker acts as the lower mantle. The top cracker, or plate, slides easily around on the softer asthenosphere. Next, learners can break the brittle lithosphere (the top cracker) in half to simulate an earthquake. Next, have them push the cracker pieces together to simulate convergent boundaries. When the pieces are slid apart, divergent boundaries are created. Sliding the pieces side by side yields transform boundaries.
This is a great way to show your class that moving plates cause many of Earth's geological characteristics, like mountains, valleys, and volcanoes. Remember, this is just the introduction to how the lithosphere is in constant motion and not a comprehensive exploration of the flow of heat and molten rock affect plate tectonics. It does however, illustrate the movement of plates and how each layers is made up of varying materials which explains why they are able to shift . It will also help teach and reinforce the different types of plate boundaries.
If hummus and crackers do not appeal to you, or you have picky eaters, here are a few other items you could use: Oreo Cookies, crackers and peanut butter, graham crackers and whip cream, or ice cream cookie sandwiches.
An understanding of plate tectonics is essential to understanding volcanic eruptions. When the earth’s plates collide on a Convergent Boundary, forcing one plate beneath the other, the pressure on the magma chamber (between the crust and the mantle) forces magma up through the conduit and out of the volcano through the vents.
A way to re-create this process with your class is to build baking soda volcanoes. You can build the volcano using a baby food jar and wrapping it in clay to create a mountain. Leave the top of the jar uncovered. Place 2 tablespoons of baking soda, 4-6 drops of dish detergent and red food coloring into the jar. Then pour about 1/4 of a cup of vinegar slowly into the jar and watch it bubble up and erupt!
The process created by the baking soda volcanoes is similar to an actual eruption because the chemical reaction between the baking soda and the vinegar produces a gas called carbon dioxide. Pressure builds inside the jar until the gas bubbles are forced out of the jar. In a volcanic eruption, the pressure on the magma chamber, which is made up of gases and rock, builds until it is forced out of the vents.
Weathering is the physical or chemical process that gradually wears down rocks. When the weathering process loosens the rock to the point that it crumbles or moves, it is called erosion.
The causes of physical erosion (gravity, ice, water and wind) can be demonstrated using mashed potatoes. A mountain of mashed potatoes can be changed, or weathered, by gravity. Tilt a plate of potatoes until the potatoes begin to shift. Gravity moves the potatoes in much the same way that it causes erosion. Weathering by water can be achieved by slowing pouring gravy or melted butter on top of the mountain of potatoes. Point out the channels and crevices that are produced. They look very similar to rivers cascading down a mountain. Freeze the potatoes and demonstrate how the pile can be broken into pieces to illustrate the kind of weathering caused by ice. Wind is a bit more complicated to show, however I have used a high-powered hair dryer and very soft-mashed potatoes, which worked nicely.
It is important to review that most weathering occurs very slowly over long periods of time. The simulations using the potatoes happens very rapidly, which can be misleading. Reinforce this truth multiple times throughout the lesson.
Let Your Culinary Creativity Run Wild
The possibilities for teaching science with culinary creations are endless! I've used oatmeal chocolate chip cookies to introduce sedimentary rocks, rock candy to explain igneous rocks and crystal formation, gelatin to explore states of matter, and various food items to explore measurement and scientific investigations. Pupils will be tuned-in and excited when learning tastes good!
Other great resources to teach geological events:
Wondering how to teach the complex parts of volcanoes? Learners will explore different attributes of volcanoes through comparing and contrasting differences between them. They will diagram its parts and use its location to determine the types of eruptions.
Weathering and erosion is explored using common household items. Young scientists build weathering simulations while practicing high-level thinking skills and scientific inquiry.