This article examines community practices, in particular oral discourse practices, in a junior high school classroom in an urban area of Western Canada. The purpose of the research was to determine what contribution a "community of practice" (COP) framework could make to the study of social interaction in a classroom setting. Qualitative research methods were used to explore student-student and student-teacher interaction in a culturally and linguistically diverse Grade 9 classroom. Of particular interest was why a language arts teacher who claimed to love teaching through dialogue rarely initiated classroom discussion. Study findings demonstrated that the teacher's practices were shaped by the social structure of the classroom community. The article explores the teacher's role in disrupting cultural practices that limit students' participation. In conclusion, the article makes an argument for scaffolding to be added to the COP framework if it is to be utilized to advantage in classroom settings and suggests incorporating hybrid literacy practices in multilingual contexts. (Contains 15 notes.)