Revising a freshman chemistry gas laws unit to enhance conceptual learning and problem solving
Date
2019
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Publisher
University of Delaware
Abstract
The University of Delaware Associate in Arts Program is a two-year undergraduate program of the College of Arts and Sciences. Students can take two sequential freshman-level one-semester general chemistry courses (CHEM103 and CHEM104), with CHEM103 a prerequisite for CHEM104. Historically, students exhibit weak problem-solving skills, as demonstrated by low exam scores. ☐ This project’s goal was to use evidence-based strategies to revise the gas laws unit in CHEM104 to enhance students’ conceptual understanding and problem-solving skills. This unit was chosen because its topics have applicability to everyday life and require extensive calculations. The project followed the methodology of design-based research. A literature search was conducted, and design principles were identified and used to guide the selection of materials and activities. The materials focused on promoting metacognition and improving conceptual understanding. The revised unit included student-centered and interactive guided activities. Simulations were included to help facilitate students’ visualization and understanding of dynamic physical and chemical processes. ☐ The revised unit was taught to 12 students over four 75-minute sessions. Feedback on activities was solicited at the end of each of the first three sessions. Student performance was assessed on a 21-question test that was administered pre- and post-unit implementation. ☐ Analysis of students’ feedback indicated that they found the activities and simulations helpful but most preferred instructor-run simulations. They also found the calculations difficult. Analysis of pre/post-test results yielded varying results. Overall, there was only a slight improvement for the percentage of students with fully correct answers. There was slightly more improvement in students’ performance on conceptual questions compared to algorithmic questions. When analyzing each question individually, results varied, with some statistically significant improvement for both lecture-based and activity-based sections. ☐ Given the small number of participants, pre/post-test findings should be interpreted with caution. However, the framework and resources developed, such as simulations and activities, and the lessons learned can be used in future revisions of other units. Students’ feedback can help initiate collaborative discussions with other instructors. Future curriculum improvement can aim to incorporate additional design principles and address social-emotional aspects of learning to reduce anxiety and improve attitudes and self-efficacy.