This case describes a three-part assignment in which students discuss key processes that regulate the stability and resilience of the Earth system and our increased risk of generating large-scale abrupt or irreversible environmental changes. Here, we use the planetary boundaries concept as a case study. Students are first asked to complete a pre-reading assignment in which they illustrate their perceptions of the degree to which human activity has changed nine earth system processes (e.g., nitrogen cycling, biodiversity loss, ocean acidification). Students then read primary literature on the planetary boundaries concept and complete a reading assurance assignment in which they summarize the reading and reflect on questions generated by the reading. In class, students work together in assigned groups to create a diagram of their collective perceptions and identify processes for which there was the largest misalignment with those presented in the paper. Students then discuss and summarize the evidence used by the authors to justify where these processes stand with respect to the safe operating space for humanity. The lesson concludes with a facilitated discussion and lecture on sustainability governance. This lesson provides students with a "capstone" activity to integrate ecological concepts discussed over the course of a semester and frames a larger discussion on socio-ecological aspects of global environmental change.

Primary image: Example of a student’s illustrated perceptions prior to reading ‘A safe operating space for humanity’ (Rockström et al. 2009). The wedges represent an estimate of the extent to which humans have changed nine earth system processes.

The five Phanerozoic mass extinctions were central in shaping biodiversity on Earth today. Due to increasing biodiversity losses, there is debate about whether we are currently undergoing a sixth mass extinction. To help students better understand these issues and explore the ongoing debate, we developed a lesson that uses active learning approaches including small-group work, poll questions, and whole-class discussion. This lesson provides an overview of major events in Earth’s history, an introduction to extinction and mass extinction, and past and present conservation efforts. Students were assessed using two short take-home assignments, in-class poll questions, and quiz questions. Here we provide detail about the lesson and summarize student performance on the assessments.

Primary image: This image was adapted from work shared under a Creative Commons License (https://commons.wikimedia.org/wiki/File:Nature_timespiral_vertical_layout.png)