Kiehl, Melissa LynnProfessional development generally refers to the collection of activities that systematically increase teachers' knowledge of academic subjects and advance teachers' understanding of instructional strategies. Given the complexity of the reform initiatives for science education in the United States of America as set forth by the American Association for the Advancement of Science (AAAS), and the National Science Education Standards (NRC, 1996), professional development might provide a bridge for aligning teacher practice with national standards (Loucks-Horsley, 1995). However, the current model of professional growth, focused largely on expanding a repertoire of skills, is not adequate (Little, 1993). Understanding teacher learning theory and utilizing research on pedagogical content knowledge (PCK) could be the differentiating factor for science teacher professional development; if utilized in design and evaluation, they may promote both knowing science in context and knowing how to tailor science learning to the needs of students (Shulman, 1987). The purpose of this study was to investigate how the Laboratory Science Teacher Professional Development Program (LSTPD), a three year professional development model that immerses teachers in learning science content through inquiry, impacts teachers' learning and classroom practice. It first aimed to analyze teacher learning and PCK; second, it examined their views on professional development; and third, whether they anticipate adapting their practice to include facets of their laboratory experience. Participants were teachers in their second or third year of participation in LSTPD. The study followed a qualitative case study design and made use of in-depth interviews and observations to examine teachers' knowledge, beliefs, and practice. The study drew on a constructivist framework. Findings demonstrated that teachers' understanding of content, inquiry, and science as a living enterprise were greatly increased, and that teachers generated goals for practice that echoed their new understandings. Further, teachers articulated how they connected LSTPD to their classrooms, fueling further discussion of the role of PCK in their experience. This study has greater implications for the design of sustained research-based professional development experiences in promoting learning in teachers, and inquiry techniques in classrooms.en-USDissertationEducation, Curriculum and InstructionEducation, SciencesProfessional DevelopmentPedagogical Content KnowedgeLearningChange