3.1. Rationale for Changing from a Traditional Curriculum

After teaching the Instrumental Analysis Laboratory course for several years, I identified shortcomings in learning outcomes that could be addressed through a project based learning (PBL) pedagogy. Specifically, I wanted to address students’ ability to achieve accurate results, troubleshoot experimental difficulties, communicate scientific results, and learn instrumentation in greater depth.

Accuracy: One course objective is that students must learn to perform an analysis with a high level of accuracy and precision. However, student motivation to perform a careful analysis may not be high if the result is not of real interest to anyone. In addition, course surveys indicate that many students do not have a high level of confidence that they can analyze an unknown amount correctly. The brewery project provides a strong incentive for students to work diligently in order to obtain the best possible results. Students become highly motivated when they directly interact with the brewery staff relying on their answer. In addition to motivation, multi-week projects allow time for procedures to be repeated if mistakes are made.

Troubleshooting: Frequently experimental difficulties arise and troubleshooting should occur to address problems encountered along the way. A great deal of learning can occur by making careful observations followed by adjustments. In a traditional setting with “cookbook” experiments, many students finish as quickly as possible and feel they can address poor results by discussing sources of error in their write-up. Many errors can be corrected if the student had time to repeat or adapt the procedure. This kind of flexibility is not typically built into a schedule where experiments are performed each week. Open ended, multi-week projects give students time to discuss problems, suggest solutions, and test new procedures.

Scientific Communication: Another course objective is the clear communication of experimental theory, procedures, and results. Analytical chemistry students frequently write journal-style lab reports, but many do not take the time think deeply about the best way to represent data in tables and graphs. Although I tried to address this problem through peer review, course discussions on writing, and short writing assignments, there was still room for improvement. I believe that motivation is an obstacle in this course objective as well. Many students do not care that much about a report that is only going to be read by their TA. Other than a grade, there is no incentive to really struggle to find the best way to communicate their results and conclusions. If the information in the report was of real use to someone, then students would be more inclined to produce high quality work.

Instrumentation: In a traditional analytical chemistry laboratory experience, students may not gain much exposure to operating and troubleshooting modern instrumentation. Due to large number of students and time constraints, often the TA tests the experiment and makes any adjustments to ensure the instrument is working properly. If problems occur, students frequently sit back while the TA fixes them. The addition of multi-week projects where students must operate and fix problems with the instruments on their own would address this deficiency. I have found that students are initially frustrated when they encounter instrument difficulties, but are thrilled when they can solve the problem. Since the projects were introduced, students routinely optimize instrument settings for their specific analysis, fix problems such as clogged AA burners, and perform general maintenance such as cleaning electrodes and changing a capillary in the CE.