Abstract: In a pre-service Euclidean plane geometry course, the teacher tries to
encourage student participation in the collective production of proofs. During
his interaction with them, he delivers different types of messages. In this article,
we present a characterization of teacher messages, which arose while analyzing,
from a semiotic perspective, teacher and student interactions within the class.
Initially, we present the theory that underlies the semiotic analysis of the dialogues;
then we discuss in detail the proposed typology. We then describe the
context and methodology of the study. As an example of the use of the characterization,
we analyze the teacher’s messages during a real class situation.
Keywords: Semiotic activity, proof, teacher’s messages, meaning making.