This report describes a study of three English teachers' and three students' participation in two high school environment clubs. Teachers' and students' interview perceptions were analyzed based a critical inquiry systems thinking framework involving inferences of purposes, outcomes, norms, and beliefs/discourses constituting energy/transportation, agriculture/food production, and economic systems impacts on climate change. Interviews were also analyzed in terms of teachers and students assuming roles in club projects and their use of tools mediating their participation in these projects. Teachers and students critiqued the purposes of systems as leading to negative climate change outcomes, as well as norms and beliefs/discourses justifying these systems. They also assumed roles related to fostering sustainability practices, including planting school gardens, supporting recycling/composting, and using tools to inform audiences about their activities. Literacy teachers can draw on the systems thinking framework for general instruction about systems impacting climate change.