Joseph Reczek, Department of Chemistry and Biochemistry, Denison University
For the full report contact Joe Reczek at reczekj@denison.edu
Introductory college chemistry classes provide a foundation of knowledge and skills upon which all subsequent classes in the Chemistry and Biochemistry curriculum rely. It therefore requires the coverage of a broad range of topics and competences which makes it challenging to offer in a cohesive way that students in a mixed-level college classroom will find relevant and engaging. The pedagogy of problem-based learning has emerged in science classrooms and teaching laboratories as a technique to engage and inspire novice students in the investigation of modern scientific challenges. However, this approach has been limited in its utility for someone teaching introductory Chemistry due to the extreme difficulty of developing basic chemistry principles within the context of advanced concepts. A potential solution to this challenge may be to expand a problem-based approach in order to encompass the majority of a course under a single unifying theme in modern chemistry. If, over the course of a semester, this specific theme that has been chosen could be broken down into fundamental elements that match well with the introductory chemistry curriculum, it would provide a cohesive and relevant context for students to simultaneously learn the essential knowledge and skills of chemistry and the modern day relevance of its practice. To test this, I developed a fully integrated theme-based inquiry (FIT-BI) approach for my introductory chemistry course (“Atoms and Molecules: Structure and Dynamics”).
This course covered all of the content traditionally taught in Denison’s introductory chemistry course (CHEM 131) while focusing on the overarching theme of recent developments in low-cost solar energy technologies. My ongoing research program is also related to the development of novel photovoltaic materials. As such, the major course goal for this novel, problem-based approach to general chemistry is to have students learn and develop an integration of general chemistry principles with cutting-edge developments in solar technology. Recent advances in the chemistry of low-cost solar energy devices, in particular Perovskite solar cells, allows for the relatively facile hands-on investigation of these emerging technologies by undergraduate students.
The solar devices theme was integrated from day one of the semester, when I constructed a Perovskite solar cell for the class and posed the question: “How is this small, low-cost device turning room light into enough electricity to run a small fan?!” While it was expected that the vast majority of first-year students had been previously exposed to the concept of solar energy, none had any idea of how it truly worked. The remainder of the first class was spent in a discussion of the energy challenges currently facing global society, and the potential solutions currently being explored by chemists and many others. From here the course was divided into three sections, with topics, discussions, problems, and labs intimately related (not exclusively) to how and why the Perovskite solar cell works, the FIT-BI approach.
The effort to fully incorporate the content and non-content learning goals of CHEM 131 into a cohesive and highly relevant investigation of cutting edge solar energy research went well beyond the expectations of a typical course revision. This was an exciting opportunity for initial development of a completely new approach to teaching introductory chemistry because there is no textbook or model available for this pedagogical project. While a daunting endeavor, this proposal connects the instructor’s passion for solar materials research with a commitment to sharing the excitement and relevance of Chemistry at even the most fundamental level. The learning goals of this FIT-BI approach to teaching introductory chemistry are the same as those for the traditional CHEM 131 class. Students will: 1) Obtain mastery of the fundamental concepts and skills of the discipline of Chemistry, 2) Learn the basics of experimental inquiry and laboratory practice, 3) Improve upon quantitative reasoning, communication, and problem solving skills, 4) Understand the importance and relevance of the field of chemistry to society and their everyday lives. However, the FIT-BI approach provides a context anchored in important real-world issues for all of these leaning goals. If executed well, this approach should enhance the outcomes of each learning goal, as there is substantial educational research showing student by-in and motivation are significant indicators of positive learning outcomes. In particular FIT-BI will impact learning goal 4, especially with respect to the long-term student outcomes.
The ultimate goal of the lab was to have students construct their own Perovskite solar cell, and this worked beautifully. Every student successfully made a working solar cell in the 3-week period of this lab, and students clearly valued the genuine experience with an ongoing research area. Leading up to making their solar cells, labs focused on elements of the whole, including measuring the absorbance of dye molecules, the conductivity of ionic solutions, and the characterization of molecular components.
The major goal of this innovation was to motivate and inspire students with the excitement of ongoing chemistry research while minimizing the sacrifice of traditional course content and learning. The results of a course survey indicated that the students were very motivated by the course ties to solar energy and solar cells. At the same time, students’ exam scores (including on questions which I used in previous general chemistry courses) were overall slightly higher than past averages.
This project was an ambitious step towards fundamentally changing how I approach teaching introductory level chemistry. I will use the theme-based inquiry approach in my future classes of CHEM 131, and I am currently thinking of ways that I can try to adapt this approach in my organic chemistry classes. A continued challenge is to find genuine ways in which the fundamental course content relates to an ongoing research thrust in modern chemistry. A fair level of expertise in the research area is necessary to achieve this over an entire semester, and the research area needs to be relatively transparent in how it relies on chemistry fundamentals. In my future course iterations of CHEM 131, I will do a better job of making these connections throughout the course, hopefully to the point that every class has a clear relationship to the research theme.
