Abstract
Teachers' knowledge and classroom teaching are strongly related to each other. Every activity in the classroom teaching comes from teachers' knowledge of subject matters. Here, the transformation of teachers' knowledge of subject matters plays a significant role. Thus, this paper reports about teachers' subject matter knowledge that is categorized into content knowledge, pedagogical content knowledge and curriculum knowledge, and its transformation into classroom teaching by Mongolian primary school teachers, focusing on the concept of fractions. The study investigated 2 groups of teachers who have common professional degrees. The transformation was identified through a hermeneutical analysis based on the characteristics of teachers' subject matter knowledge and classroom teaching that are revealed through a questionnaire and classroom observation. It is concluded that when the teachers transform the subject matter knowledge into classroom teaching, they emphasize one of the three categories of knowledge; and in accordance to this emphasized knowledge, relation among the three categories of knowledge is modified in the process, and thus the modified subject matter knowledge is able to characterize his/her classroom teaching.
