Conceptual change as a professional development model has moved elementary science teaching beyond lecture and the memorization of facts to science instruction congruent with the National Science Education Standards (National Research Council, 1996). However, research on the effectiveness of conceptual change teaching reveals some of its limitations. Specifically, little is known about the influence of conceptual change teaching on African American teachers' science pedagogy with African American students. This study employs case study methodology to explore the influence of science education professional development based on the conceptual change model of teaching on teachers with varying levels of science education experiences, science content knowledge, teaching experience, and leadership experience. The study addresses the following questions: (1) How do African American teachers describe the influence of a science education professional development program on their teaching of science to African American students? (2) How do African American teachers describe their beliefs about conceptual change teaching after participating in professional development programs? (3) Is there a relationship between self-reported conceptual change teaching practices and actual classroom practices? (4) Is there a relationship between reported changes in conceptual change teaching practices and the content of the professional development institutes? Ethnographic data were obtained from classroom observations and semi-structured interviews with seven African American educators teaching elementary science in an urban school district. These data were collected following these lead science teachers' four year of professional development in a science education professional development program. Findings from the study indicate that African American teachers who participated in the science education professional development program incorporated several tenets of conceptual change in their science instruction. These included the use of questions (recall), hands-on activities, and collaborative groups. This study also revealed that African American teachers used their knowledge of African American students' cultural experiences to teach science. The African American teachers used culturally specific analogies, praise, and motivation in ways that extended beyond their professional development training. The teachers incorporated numerous affective pedagogical strategies, which are often not observed in the more cognitive domain of science teaching. The findings of this study have implications in educational curricula, teacher professional development, and on science classroom practices. (Contains 4 tables.)