During the COVID-19 quarantine, we conducted a field-setting pre/post-test randomized experiment (n = 115), creating a community using the social media application Instagram to enhance students' interactions with their peers and immediate physical environments in a large, introductory online course in environmental psychology. We used the framework of the community of inquiry (CoI) to explain the ecological effects of this project. After posting photos and interacting with others on Instagram weekly for 8 weeks, student participants reported a significantly greater social presence and cognitive presence. Furthermore, participants reported higher levels of course satisfaction and performed better on the preliminary exams than non-participants, but this does not seem attributable to the intervention itself. We discuss the issues of self-selection bias, attrition bias, and compliance bias in this study arguing that greater social presence increased the cognitive presence, as mediated by meaningful peer interactions. Our findings provide additional evidence on the value of using social media in educational settings on learning experiences and for building communities to connect students with their peers and physical environments. We also explore the implementation of a pedagogical approach to context-based learning via mobile technologies, and how the CoI framework can be used in evaluating online learning environments.