IU course about geologic time featured in the Journal of College Science Teaching
Students Alicia Pardoski, Adelye Seng and Bayli Payne, from right, confer with associate instructor Will Simmons, left, during a recent lab in professor Chen Zhu’s environmental geology course.
Faculty and staff show how integration of course learning outcomes with active learning techniques and course assignments helps students gain an understanding of geologic time.
They suggest the approach can help students overcome similar “bottlenecks” that prevent in-depth learning in other fields—just as students in an undergraduate class in environmental geology gained basic understanding of geologic time and grew confident in their ability to use the concept.
Their article, “Looking Back to Move Ahead: How Students Learn Geologic Time by Predicting Future Environmental Impacts,” was published in the current issue of the Journal of College Science Teaching. Authors are professor Chen Zhu and associate professor Claudia C. Johnson of the Department of Geological Sciences; George Rehrey, a consultant with the Center for Innovative Teaching and Learning; and Brooke Treadwell, a graduate student in the School of Education.
Zhu said comprehending geologic time is often a big challenge for students, especially those without a strong science background. It’s hard for them to make sense of processes that take place outside the scope of their own lives, much less over many thousands of lifetimes.
The problem presents a “bottleneck,” a term coined by IU scholars David Pace and Joan Middendorf and colleagues in their Scholarship of Teaching and Learning research on “decoding the disciplines” to describe the place where many students get stuck and can’t progress to expert-level thinking on a given topic or key concept.
“In this case, if students can’t understand and apply the immensity of geologic time, they aren't going to succeed in the course,” Rehrey said.
In the environmental geology course, designed for non–science majors, Zhu used labs and projects in which students created “distance metaphors” to visualize the immensity of geologic time: that the Earth is nearly 4.6 billion years old, that dinosaurs and other organisms evolved and went extinct over periods of hundreds of millions of years, etc. For example, students used rolls of toilet paper and paper towels to represent units of geologic time, demarcating events in the Earth’s past.
