| The purpose of this study was to describe the evolution of pedagogical content knowledge in prospective secondary chemistry and physics teachers. A new paradigmatic framework was developed to guide the research. Craft knowledge and pedagogical content knowledge were compared and combined forming a new perspective from which to view secondary chemistry and physics teachers' "learning to teach." A second purpose of this study was to develop philosophically-derived, domain-specific, pedagogical content knowledge taxonomies. Four taxonomies were developed in all; two general and two domain-specific. The general taxonomies describe types of pedagogical content knowledge and attributes of pedagogical content knowledge. The two domain-specific taxonomies describe topics common to both physics and chemistry and outline domain-specific laboratories for the differentiation between heat and temperature.;A methodological theoretical framework, synthesized from radical and social constructivism, was developed to guide the researcher in data collection, analysis, and interpretation. The researcher used four cases, two prospective chemistry teachers and two prospective physics teachers, and followed their development through the science curriculum class and student teaching field experience of their teacher preparation program. Content-specific, situational vignettes were created as a tool to monitor the participants' development of pedagogical content knowledge. The vignettes were administered using a modified microgenetic method. The modified microgenetic procedure involved the repeated administration of a task (vignette) over a period of time to monitor cognitive change. Data were collected through several methods: participant responses to the vignettes, field notes taken during the science curriculum class and student teaching field experience, interviews, artifact collection, and journals. Data were analyzed using qualitative content analysis.;The results of this study support five major findings about the development of pedagogical content knowledge in prospective secondary chemistry and physics teachers. First, prospective teachers developed various types of pedagogical content knowledge. Second, the development of topic-specific pedagogical content knowledge occurred before domain-specific pedagogical content knowledge. Third, the prospective chemistry and physics teachers believed that experience in the classroom was an integral part of their development of pedagogical content knowledge. Four, prospective teachers became student centered in their teaching approach, developed a holistic view of science teaching and learning, and began to reflect and philosophize about their beliefs of science teaching and learning. Finally, the prospective teachers demonstrated and developed foundational understanding of science teaching and learning that would serve as a building block for further development of domain-specific pedagogical content knowledge.;The development of taxonomies and related nomenclature was supported by findings in this study. The development of pedagogical content knowledge was determined to be complex and non-linear In particular, content knowledge, followed by knowledge of students, were determined to be the most important knowledges in the development of pedagogical content knowledge. Knowledge of content and students formed a base from which prospective teachers could develop domain-specific pedagogical content knowledge. |
