What tools do you need to be a geologist? A straw, a toothpick, and a cookie are all Hettie Halstead Elementary School third-grade students needed for their hands-on science experiment in geology to learn about erosion and weathering.
Teacher Swantje Drayton wanted to engage her students in learning about weathering through the use of a visual and applied activity to represent how the earth changes.
“Weathering is such a hard concept for students to master because we cannot just go outside and observe how a rock weathers in a natural cause over a long period of time,” Drayton said. “Slow changes to Earth’s surface are such an abstract concept for third graders.”
Texas students are required to explore and record how soils are formed by the weathering of rocks and the decomposition of plant and animal remains. To incorporate these Texas Essential Knowledge and Skills into her lesson, Drayton had the students tackle an investigative assignment and record their observations about how weathering caused by water, wind and plants change rocks and rock formations.
Third-grader Allison Young said the class assignment was “the best science experiment ever.”
“I thought the best part of the experiment was when we got to use the toothpick to show how plants can weather rocks,” Young said.
During the experiment, substituted cookies for rocks. Students blew through straws to simulate wind and then took the cookies apart with toothpicks to represent how the pressure from roots from trees, bushes and flowers change the rocks.
Finally, students dripped water on their cookies to show the effect of water in the weathering process.
Throughout the experiment, the students made connections and recognized how the cookies represented the earth and how weather and nature can cause it to change.
“Now, it makes sense that I see flowers and weeds breaking through rocks,” Young said. “I just didn’t know that it was called weathering.”
After the students had completed the assignment, they noticed the cookies were completely weathered away by the water. They were able to observe with just straws, toothpicks and cookies how the wind, water and roots impact the ground they walk on every day.