摘要：The purpose of the study was to examine the pedagogical content knowledge of middle school mathematics teachers based on its components: subject matter knowledge, knowledge of student, and knowledge of instructional strategies. The purposive sampling method was used in the study with the design of case study. The participants were composed of six middle school teachers having different number of experienced years. The data triangulation was made by using the techniques of semi-structured interviews, semi-structured observation and document analysis. Throughout implementation, audio recordings of all of the interviews and video recordings of observations and lessons of three teachers were collected. In this study, qualitative data analysis techniques were used. Nvivo 8 software package was used in order to analyze subject-matter knowledge. At the end of the study, it was found that most of the teachers had lacking or incorrect knowledge about component of subject-matter knowledge about cone. On the other hand, results showed that mathematics teachers' knowledge of student was sufficient. Furthermore, it was found that the teachers could not sufficiently use the strategies to have the students participated in the process such as "Discovery Learning".
关键词：Cone; subject-matter knowledge; knowledge of instructional strategies; knowledge of ; understanding students; mathematics teacher
