Abstract
How can we help teachers to communicate their metaknowledge, especially, the nature or character of mathematical knowledge or activity to the students? We regard this as the central research question of our study. The present paper can be understood as an attempt to try to ask the question through consideration of practices in the classroom. To do so, a cooperative teaching experiment was conducted over a four-week period including 4 lessons with an 8th grade class on June 9, 12, 13, and 16 in 1995. The analysis of interaction between the teacher and the students in the lessons revealed that when (1) the teacher helped students to develop their thinking tools which they already have used to approach the task concerned, and further (2) the developing their thinking tools enabled students to be aware or discover what they did not know, the teacher's metaknowledge could be communicated to students.
