| This study explores how teachers develop their knowledge in the domain of pedagogy? Specifically, it has two research questions: (1) Are there different sources of teachers' pedagogical knowledge? (2) How do different sources contribute to the development of teachers' pedagogical knowledge?;Utilizing NCTM's description, this study categorized pedagogical knowledge into three components: pedagogical curricular knowledge (PCrK): knowledge of teaching materials and resources, including technology; pedagogical content knowledge (PCnK): knowledge of ways to represent mathematics concepts and procedures; and pedagogical instructional knowledge (PIK): knowledge of teaching strategies and classroom organizational models. The study takes into account the whole life of teachers, including their learning experiences, preservice training, and inservice experiences, to investigate the sources from which teachers develop their pedagogical knowledge.;The research subjects are 77 mathematics teachers in three high-performing high schools, a stratified random sample from the 25 best high schools in the metropolitan area of Chicago. The instruments include a questionnaire, classroom observation, and interviews. Both quantitative and qualitative methods were employed to analyze the data.;The findings of the study reveal that there exist various sources from which teachers develop their pedagogical knowledge. Within different sources, the study found that overall teachers' "own teaching experience and reflection" and their "daily exchanges with colleagues" are the two most important sources for them to develop all three components of pedagogical knowledge. "Inservice training" and "organized professional activities" are also relatively important sources. But teachers' previous "experiences as students", "preservice training", and "reading professional journals and books" are the least important sources.;The findings of the study indicate that, for teacher educators, it is necessary to take substantial steps to reform preservice education programs and equip prospective teachers with more and newer pedagogical knowledge and skills; for school administrators, it is very important to promote teachers' daily exchanges with their colleagues in seeking teachers' professional development; and for teachers, they need to be lifelong learners of how to teach more effectively and be reflective (of experience), accumulative (of knowledge), associative (with colleagues), and attentive (to various sources) in seeking to develop their pedagogical knowledge. |
