PETROGRAPHIC PROBLEM-SOLVING ASSIGNMENTS: AN AUTHENTIC ASSESSMENT STRATEGY FOR UNDERGRADUATE PETROLOGY COURSES
PPS assignments serve as an authentic assessment strategy in two upper-division Earth Science courses. Students are introduced to PPS assignments in a prerequisite Microscopy course. In the subsequent Petrology course, three assignments are conducted, and a summative take-home PPS exercise is completed as part of the final exam. PPS assignments are directly aligned with course content in Petrology and are designed to augment traditional assessment strategies. To determine whether the learning goals of PPS assignments have been met, student work is evaluated in terms of application of scientific methodology, problem solving, and communication skills. Analysis of assessment data collected over a six-year period shows that student performance improved over the course of each term by 4.5% on average (n=53), demonstrating increased proficiency in conducting authentic investigations, solving geologic problems, and communicating results. As a key component of the mineralogy-petrology curriculum in a broad-based undergraduate degree program, PPS assignments engage students in the study of Earth materials, involve them in the scientific process, and promote active learning with an emphasis on analysis, synthesis, and evaluation.