This paper focuses on a brief whole-group conversation captured in a sixth grade classroom taught by an experienced teacher. Drawing upon systemic functional linguistics, it treats the conversation as a multi-semiotic text of the genre of teacher-guided mathematics problem framing. After describing the generic structure of the text and its context of situation, it analyzes the ideational, interpersonal, and textual meanings students and teacher contributed to its conjoined making. The analysis shows how the text means as it does and, in so doing, underlines those features that make it a paradigmatic instantiation of its genre. The paper concludes by highlighting the contribution of systemic functional linguistics to current conversations about thought and language, dialogue and representation, and context and text.