HANDS-ON EXPERIENCES WITH STABLE ISOTOPES IN THE GEOSCIENCES CURRICULUM

Over the past thirty years, environmental and geoscience research has increasingly utilized stable isotope ratios to understand problems as diverse as paleoclimates, magma genesis, and processes in the hydrosphere and critical zone. New laser-based technology for measuring isotope ratios has significantly reduced the cost of setting up and maintaining an isotope lab. The new technology is also easier to use with students than traditional isotope ratio mass spectrometers, so there is strong potential to introduce hands-on experiences into the geoscience curriculum.

This project, funded by the NSF Division of Undergraduate Education, assessed the impact that different pedagogical approaches have on student learning of stable isotope concepts in upper-division geoscience courses (Watershed Hydrology; Sedimentology/Stratigraphy; Environmental Geochemistry). Groups of students were exposed to this content via (1) a lecture-only format; (2) a paper-based data analysis activity; and (3) hands-on data collection, sometimes including spectrometer analysis. Pre- and post-tests measured gains in content knowledge while approaches to learning and motivational questionnaires instruments were used to identify the effects of the classroom environment on learning approaches and motivation. Focus group interviews were also conducted to verify the quantitative data. Preliminary findings of this study, currently in year two of three, include: a) a common decrease in student motivation as the semester progresses, b) relatively minor changes in student approaches to learning regardless of pedagogical strategy, and c) students’ positive responses to professor passion.

Peer review of modules and activities has been used to ensure high quality content is being delivered. Close collaboration between geosciences and education faculty at all project stages has enabled deployment of robust measures of student learning, increased responsiveness of the research to developments in the classroom, and facilitated exploration of unexpected project results. In its final year, the project will focus on high-impact dissemination of developed curriculum and project results, through workshops and on-line repositories.