From Aquifers to Goo, Event Encourages Girls' Interest in Science and Engineering
At the end of February, 160 local fourth through sixth grade girls spent their Saturdays at Duke exploring science with a creative twist, including topics ranging from the pollution of groundwater in underground aquifers to the chemistry of goo.
The event marked the second annual Females Excelling More in Math, Engineering and Science (FEMMES) organized by Duke junior and psychology major Vicki Weston. This year’s day-long program included activities led by several faculty members representing Duke and the Pratt School of Engineering, as well as Duke’s chapter of the Society of Women Engineers (SWE).
A Gooey Lesson
“Today, we’re going to be making goo,” one SWE member said to a small group of girls during the first activity session of the day. “But first, let’s talk about the states of matter: solid, liquid and gas.”
The girls each offered an example, or picture, of the familiar states and the subject turned quickly back to goo.
“The goo we’re going to make is special,” the girls were told. “It’s not just one form. When you squeeze it hard, it acts like a solid, but if you let it run it turns to liquid.”
The girls all got busy mixing corn starch and water in Dixie cups to make the special goo before letting what seemed like a solid glob slowly ooze over their fingertips.
Meanwhile, across the room, other SWE members led another group of girls through a marshmallow and toothpick tower-building exercise. Their towers were tested for strength by placing objects on top of them, a launching point for a discussion on architectural engineering and building techniques for optimizing height and strength.
The SWE session was one of 12 activities -- from one titled “What’s up with those crazy termites?” to explorations of ultrasound imaging and the chemistry of the earth — that FEMMES participants could choose to attend during any one of the day’s four sessions.
Build Your Own Aquifer
Civil and environmental engineering Professor Helen Hsu-Kim teamed up with the Nicholas School’s Heather Stapleton, both experts in the study of environmental pollutants, for a primer on the water cycle and a demonstration revealing how groundwater stored in underground aquifers can become polluted by chemical fertilizers or pesticides.
“Water percolates through the ground into aquifers Â–— underground pools of water,” Hsu-Kim explained. “Groundwater is really clean and good to drink, but it can be polluted. We’re going to think about how that happens and how to prevent it.”
The girls who were participating in FEMMES gathered in Stapleton’s laboratory to “build their own aquifers” in a small aquarium. Stapleton and Hsu-Kim adapted the activity from one devised by the U.S. Environmental Protection Agency.
The model aquifers consisted of layers of sand, Play-Doh and rocks, representing the layers of the earth, topped with a piece of green felt, which Stapleton referred to as a model “golf course.”
The girls then sprinkled “pretend pesticide” (actually red Kool-Aid) on the greens and began delivering "rain" by spray bottle onto the mock pesticide-laden grass, watching as the Kool-Aid red polluted their model groundwater.
Drawing the Invisible
That afternoon, in a session led by Rebecca Willett, an assistant professor of electrical and computer engineering, still other students learned about ultrasound imaging through a hands-on experiment to “create a picture of what you can’t see.”
“Ultrasound imaging is used to create detailed pictures of the inside of our bodies without performing surgeries,” Willett said. “These images are created by sending sound waves into a person’s body and measuring how they bounce off internal organs and other structures.”
To explore the concepts and mathematics behind these images, the girls sent long, slender poles into a linear series of holes fashioned on the sides of wooden boxes. By measuring and plotting the distance the sticks traveled into the box before hitting the mystery contents within, the girls created a rough image of the hidden object without having seen it directly.
Said FEMMES founder Weston of this year’s program, “I was just really blown away by how smart and enthusiastic our participants were. We also got a lot of comments from parents and kids that they had a great time and were more interested in science now, which is, of course, the goal.”