UC Berkeley

Climate change and the resulting and related environmental and humanitarian outcomes are some of the fundamental challenges of the 21st century. Green chemistry, a relatively recent addition to the chemistry family, aims to reframe chemistry so that chemistry ethically and responsibly attends to its own environmental and human health impacts and becomes a contributor to sustainable development and innovation within and outside of chemistry. Integrating green chemistry in undergraduate education provides students with an ethical framework for doing chemistry, gives more meaning and relevance to chemical learning, showcases new ways of approaching chemical problems, and allows students to participate in more authentic problem solving and inquiry.

The general chemistry classroom is an ideal yet often underused course for introducing students to green chemistry – especially for non-chemistry majors who may not take any further chemistry courses. One major goal of this dissertation was to develop a robust green chemistry curriculum for the wide-reaching non-chemistry majors’ general chemistry laboratory course at UC Berkeley. This was an opportunity to introduce more explicit green chemistry content and practices into the general chemistry laboratory all while utilizing a constructivist learning science framework – knowledge integration – to design a green chemistry curriculum that attended to both content and pedagogy. Additionally, this curriculum work leveraged the Berkeley general chemistry laboratory structure to engage in iterative curricular revision through a utilization-focused evaluation design. Together, this work contributes to a larger understanding of how to develop coherent green chemistry curricular materials and efficiently assess and revise the curriculum by carefully evaluating the implementation process and resulting student outcomes.

The second focus of this dissertation was to develop a series of fixed and free-response items to probe different facets of green chemistry ability (both green chemistry content knowledge and practices) that could be administered and analyzed for thousands of students. While many green chemistry courses do assess student attitudes and self-reported learning more work is needed to measure demonstrated understanding of green chemistry. Even when methods other than self-reported items are used (e.g., achievement tests, course assignments) they often do not focus on green chemistry outcomes but rather general science or lab technique/skill outcomes. Especially for large enrollment courses, alternative modes of assessment, such as short answer and multiple-choice content questions, are needed to assess green chemistry student learning outcomes more fully. Thus, nearly a dozen fixed and free-response green chemistry items were created to examine how students were able to define and use green chemistry and make green chemistry decisions. Additionally, additional Likert and Guttman items were iteratively designed to measure students’ self-reported green chemistry ability, and several open-ended reflection items were used to examine how students valued green chemistry.

Overall, the results of this analysis showed an increased ability to define green chemistry and apply green chemistry concepts to a novel scenario after completing the green general chemistry laboratory course at UC Berkeley. Students reported that their ability to define green chemistry and green chemistry principles, identify and reduce hazards and waste, and identify factors that make a reaction green all increased significantly after completing the general chemistry laboratory course. Many students also reported that green chemistry was the most valuable component and most meaningful connection of this introductory course. However, not all green chemistry terms were equally easy for students to integrate into their existing knowledge schema. More targeted instruction is needed for green concepts that already have usage or meaning in general discourse. Additionally, while students entered the general chemistry course with various levels of prior green chemistry understanding, almost all students made gains in green chemistry understanding after completing the course. These gains were even across gender, underrepresented minority status, and first-generation college status.

Finally, this research showed that both general and organic chemistry students engaged in sophisticated green chemistry reasoning when provided with traditional and green data and metrics. When asked to decide between two alternative methods students used the given data to justify their choice in ways that showed their green chemistry knowledge and modes of reasoning. Overall, both general and organic chemistry students’ overwhelmingly chose and correctly justified the ‘greener’ method choice – showing similar value for and ability in making green chemistry decisions. This was especially impressive given that organic chemistry students received no additional green chemistry instruction through their chemistry courses after general chemistry. The fact that organic chemistry students would choose the green chemistry option on a high-stake summative exam indicated the value they still held for green chemistry and the confidence they had in their understanding of green chemistry principles and practices even two or more semesters after learning about green chemistry.