Abstract
Research into student conceptions in science has resulted in a wealth of findings about the ways students think and, because the research methodologies and contexts of studies often differ, these findings have not always shown themselves to be consistent with each other. However, according to the phenomenographical perspective (Marton 1981, 1984, Marton and Booth 1997), inconsistent findings on student understandings of a scientific concept are inevitable, because student conceptions themselves naturally vary from context to context and from student to student. Thus, it becomes important to synthesize various findings by describing their variations in order that meaningful categories of student conceptions can be developed. This paper proposes a methodology digraphing useful to this very purpose. The procedure includes the following: the identification of studies; the summarizing of research findings; the identification of concepts and the relations among them; the construction and clustering of digraphs; and the development of categories. To illustrate the digraphing process, research has been synthesized into student conceptions of matter. The synthesis findings are used to describe how categories can be developed. In the final section of this paper, a discussion of some validity and reliability issues related to the digraphing methodology for synthesizing research studies is presented.