This paper examines the oral and written discourse processes in a high school physics class and how these discourse processes are related to sociocultural practices in scientific communities. The theoretical framework is based on sociological and anthropological studies of scientific communities and ethnographies of classroom life. The use of discourse analysis as a methodological orientation in science education is reviewed and a logic-of-inquiry framing is provided to show how discourse analysis was used in the ethnographic research. The ethnographic analysis showed that, through students' participation in creating scientific papers on the physics of sound, their appropriation of scientific discourse was related to the framing activities of the teachers and the social practices established over time in the classroom. Textual analysis of the student papers focused on how they used evidence to make claims. The lessons learned from participating in the classroom of these students are explored. (Contains 80 references and 10 figures.) (PVD)