This project is investigating students' and experts' conceptual understanding of plate tectonics. Because plate tectonics is the conceptual model through which most dynamic processes on Earth are understood, a solid understanding of the basic tenets of the model is crucial in developing future geoscientists and a scientifically literate public. The overarching goals for this project are to 1) highlight specific concepts that pose barriers to students' comprehension; 2) make faculty aware of the extent of the problem by disseminating results in presentations and journal publications; 3) investigate whether or not the complexity, interdisciplinarity, and the continual evolution of the plate tectonic model leads to alternative conceptions being embedded within instructional tools, with the potential for passing these alternative conceptions on to current undergraduate and graduate students; and, 4) improve educational practices by making instructors aware of common alternative conceptions held by students as well as problems with equivocal representations in figures, and by suggesting alternative approaches to teaching about plate tectonics using images. Lecture Tutorials are being developed that specifically target alternative conceptions and problem areas revealed in the research. The Lecture Tutorials will be disseminated via publication and through a faculty workshop at a national conference. This project impacts several communities, including geocognition researchers, faculty and students. This project is contributing to the STEM education knowledge base by generating a unique, comprehensive data set of plate tectonics conceptions across the expert-novice continuum. Additionally, this work is having significant implications for future geoscience education practice and research, by providing insight into the importance and impact of commonly used illustrations for development of conceptual models.
Because plate tectonics is the conceptual model through which most dynamic Earth processes are understood, a solid understanding of the basic tenets of the plate-tectonic model is crucial in developing future geoscientists and a scientifically literate public. Our overarching goals for this project were to 1) highlight specific plate-tectonic-related concepts that pose barriers to students’ comprehension; 2) investigate whether or not the complexity, interdisciplinarity, and the continual evolution of the plate tectonic model leads to alternative conceptions being embedded within instructional tools such as textbooks and figures; and, 3) improve educational practices by making instructors aware of the common alternative conceptions held by students by documenting problems with equivocal representations in figures, and by suggesting alternative approaches to teaching about plate tectonics using images. We were able to identify commonly held alternative conceptions by having post-secondary students and faculty members complete questionnaires or participate in one-on-one interview sessions. Participants were from a number of higher-education institutions: two-year colleges, regional four-year universities, and private universities. These data enabled us to document widespread, common alternative conceptions such as: The mantle consists of melted rock; The ‘ends’ of subducting slabs that seem to just disappear in most images of subduction zones represent melting of the entire subducting slab deep within the mantle; and, Most melting in the mantle is caused because rocks get hotter as they go deeper into the mantle or because of friction between tectonic plates. Other common issues include: Words, such as lithosphere and asthenosphere, which are important for understanding Earth’s interior, are oftentimes confusing to students; Aspects of images, such as the red, orange, and yellow colors that are commonly used to indicate the hot temperature of the mantle contribute to people’s alternative conception that the mantle is molten. Many individuals hold complicated alternative conceptions about motions along transform boundaries; and, Students and faculty who are shown the same schematic image focus on completely different aspects of the image. This has the effect of students not seeing the image in the way that an instructor expects them to be seeing it. Our research revealed that geoscience graduate students and faculty members can retain many of these alternative conceptions. Documenting not only the breath of alternative conceptions but also that some of these conceptions are retained well beyond the undergraduate-student level points to the concerning potential for instructors to pass these alternative conceptions on to current and future students. Our findings lead us to recommend that the topic of plate tectonic fundamentals be explicitly revisited in multiple classes. Figures that are used to teach plate tectonics need to be carefully scrutinized and many of them need to be revised. In particular, aspects of images that induce or reinforce alternative conceptions such as slab tips that fade away or a mantle that is colored red, orange, or yellow need to be changed. Furthermore, we encourage faculty members to consider modifying their teaching by incorporating multiple instructional strategies. One example of an engaging resource is the Lecture Tutorial. Lecture Tutorials are in-class, interactive worksheets that require students to work with their peers to answer sets of short questions. The worksheet activities are integrated into the lecture, thereby providing students with immediate feedback. To disseminate our findings, we have conducted workshops, and given presentations to geoscience departments and at national conferences. We have also published research articles, and incorporated our findings into Lecture Tutorial-based geoscience textbooks. This project is contributing to the Science, Technology, Engineering, and Math (STEM) education knowledge base by generating a dataset of alternative conceptions related to Earth's interior and the plate tectonic model. Additionally, this work can inform future geoscience education practices by providing insights into effective approaches for teaching plate tectonics.
