Learning communities, a small cohort of students enrolled together in two or more linked courses, have become a popular intervention to help underprepared students succeed in college. Though learning communities abound in practice, the key structural feature of a learning community--the cohort--may not be fully understood. Authors posit that a cohort needs both a structural and communal component to function well. This study examines qualitative data from a pilot site and four community colleges that participated in a random assignment evaluation. Authors observed differences between learning community and non-learning community experiences in terms of classroom climate and academic support networks for students. Differences can be attributed to both the structural nature of the cohort as well as emergent social group dynamics. As such, the cohorts within learning communities appeared to act as mechanisms for increasing student interaction and interdependence. The authors anticipate that these gains in the student experience will enhance student retention. (Contains 2 tables and 4 footnotes.)