Abstract
The purpose of the study was to explore teacher behavior when playing the role of moderator in teaching conjecture in mathematics. A teacher was selected as a case study. The case was a sixth-grade teacher experienced in teaching conjecture. Collected data included six lessons of factors and multiple units. The analytical framework is based on the ownership of activities and ideas to form the role of teachers in the four quadrants, and the third dimension is added to represent the five stages of conjecture teaching. The role discussed in this article focuses on quadrant II-Moderator, which is characterized with the teacher having ownership of the activity and the student having ownership of thought. The results indicated that the role of the moderator frequently occurred in the validation stage, followed by the justification stage and formulation stage. Teaching behaviors consisted of recognizing, comparing, and integrating. In the formulation stage, the moderator asked students to compare their own conjectures with those of others. In the validation stage, the moderator asked students to express their position. In the justification stage, the moderator called for an inclusive relationship among the generalized conjectures. Students were required to compare in the formulation stage as the case teacher asked them to look at additional mathematical relationships, whilst they were required to compare in the validation stage to clarify the similarities and differences of the premises among the conjectures. In the justification stage, the case teacher asked students to compare in order to sequence the conjectures to be justified. In the validation stage, students were asked to integrate or select the most complete and representative conjectures.