Recent research has a common and persuasive vision of classrooms as a site for discursive practice. This study investigates how Japanese linguistic conventions are performed in classrooms in ways that may privilege certain participation structures in classroom practice. Japanese value implicit communication, requiring speaker and listener to supply the context without explicit utterances and cues. In Japanese discourse, agency or action are often hidden and left ambiguous. This tendency is typically found in leaving sentences unfinished. Such culturally specific linguistic traits are different from English. In English, when introducing a definition, the teacher might employ a do-verb: “We define”. In Japanese classrooms, the teacher often introduces a definition in the intransitive sense as if it is beyond one’s concern. Such differences in the location of agency, embedded in language use, constitute a different participation structure in classroom practice. Analytical tools of ethnomethodological conversational turn allocation in the classroom may need to be reexamined in light of Japanese culturally-grounded linguistic traits. The reflexive relationship between discourse structure and participation structure will be illustrated with data collected using the LPS research design.