In this article, the author concludes her article on encouraging co-operative talk in mathematics lessons. In order to assess the impact of "professor points" on the class, the author taped a session between a small group. In this discussion the children are clearly not only exploring the maths problem, but also the nature of co-operative talk.…

Four short lessons on Boolean Algebra were recorded on video tape. A week later the participating students were shown the tapes and asked to comment. Responses to the interviewer were recorded, transcribed, and interpreted. (SD)