The authors conducted ethnographic research to provide deep understanding of the learning environment of a selection of computer science classrooms at a large, research university in the United States. Categories emerging from data analysis included (1) impersonal environment and guarded behavior; and (2) the creation and maintenance of informal hierarchy resulting in competitive behaviors. Both of these categories describe patterns of recurring communication taking place in the classroom learning environments. We identify particular and recognizable types of discourse, which, when prevalent in a classroom, can preclude the development of a collaborative and/or supportive learning environment. Alternative communication choices, both explicit and implicit, can lead to a more balanced and supportive climate for learning. An example of a successful effort to alter traditional patterns of interaction, without compromising the quality of learning, in a higher education astrophysics class is presented. (Contains 1 table and 3 figures.)