The Kitchen as a Laboratory

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Categories: GSI Online LibraryTeaching Effectiveness Award Essays

by Naomi Kohen, Materials Science and Engineering

Teaching Effectiveness Award Essay, 2008

In the fall of 2007, I was a GSI for Engineering 45: “Properties of Materials.” E45 has a lecture and lab component and it is a required introductory class for many engineering majors. GSIs for this class are responsible for leading the lab sections. While the lectures were suffused with anecdotes from industry and everyday applications of materials science, the lab curriculum had not been updated for quite some time. The lab curriculum focused solely on metals, ceramics, and other classes of materials more relevant to previous decades, during the emergence of the modern field from the study of mining and mineralogy. Today, research in soft materials, such as polymers, has given the field a broader scope.

In order to address the limited scope of the lab curriculum, I designed and added “extra credit” lab demos for the lab modules. Each extra credit demo was structured so that it would teach the same concept as the lab module, but in a soft materials system. The extra credit labs provided the students with two educational benefits. In terms of content, the students were now able to do experiments on the soft materials they had learned about in the lectures. More importantly, the new lab structure helped students acquire critical thinking and reasoning skills. By learning the same concept in different systems, the concept was reinforced via repetition. Students had to use abstract reasoning to understand why the concept was relevant in both systems and how the particulars of each system lead to the concept being manifest uniquely in each system.

In order to make the demos more relevant and interactive for the students, all of the soft material systems examined were food-based. Since these systems contained familiar products, the students would feel more at ease handling them, they could use their personal experience with these products to predict some of their behaviors and relate them to the scientific concepts they were learning. In addition, the promise of a lab that yielded edible results provided an effective motivation for the students to stay for the extra credit labs. Key concepts such as phase diagrams (thermodynamics), phase transformations (kinetics), and the overarching theme of materials science, which stipulates that structure, processing, performance and properties are all dependent on each other, had only been taught using metals in the old lab modules. Some examples of lab demos I constructed included making whip cream and butter phases out of cream in order to learn about phase diagrams, processing ice cream in two different methods to learn about “nucleation and growth” and the connection between processing and performance. We also studied sugar solutions (candies and caramels) in order to learn about recovery, re-crystallization, and grain growth phenomena and to once again examine the connection between processing, properties, and performance.

In addition to the extra credit demos, extra credit questions were assigned to ensure that the students understood the demo and its relevance to the main lab module. Furthermore, the extra credit demo and questions required outside reading from the students, which helped them develop research skills.

Showing students that science occurs all around them in their daily lives, in places as familiar as their kitchens, and not just on pre-processed 1″ x 4″ metal slabs, proved to be a successful undertaking. Nearly every student participated in the food demos and nearly every student answered the extra credit questions. The students reported favorably about the extra credit labs on their GSI evaluation forms and students had personally thanked me for making the material more “fun” and literally edible.