Abstract
The present study examined the effectiveness of cooperative discussion of hypothesis testing in a sixth-grade science unit (10 hours) on "the nature of water solution" from the viewpoint of a combination of quantitative and qualitative methods. The result from a questionnaires analysis of the conceptual change between pre-post tests, and a coding analysis by the transactive discussion (Berkowitz & Gibbs, 1983) of the verbalization activities generated from cooperative learning during discursive processes among groups, indicated that (1) in the hypothesis testing sessions, overlapping conversation appeared to be significant for the construction of scientific conception. (2) in the post test, verbalization activities that were elaborated and disputed among members were appropriated into individual knowledges.
