The paper refers to the theoretical establishment and brief presentation of collaborative action research with the characteristics of "developmental work research" as an effective methodological approach so that science teachers develop themselves professionally. A specific case study is presented, in which we aimed to transform the basically monologic discourse of teacher-pupil interactions to a more collaborative, investigative one by engaging teachers-researchers in the analysis of their own discourse practices. The engagement of teachers-researchers in collaborative action research and, more specifically, in the analysis of their own discourse and the way they worked with, collaborated with and guided their pupils in science lessons proved to be an educationally creative, effective process in their training. The study and analysis of the data, which took place after the active participation of the teachers-researchers, showed that that teachers and pupils can develop desired, collaborative, dialogic skills and meta-skills on the basis of utilizing certain strategies. The most significant strategy, which was utilized during collaborative action research, was discourse analysis not only as a study tool of social school reality but also as a training, reflective, meta-didactic tool.