This study was undertaken to investigate how individual teachers' opinions and beliefs serve as a basis for classroom practice and curriculum decision making. United States history teachers are not passive transmitters of knowledge; they bring their own experiences, beliefs, attitudes, and ways of looking at the world to the classroom. The findings discussed here are based on information gained from a previous study, and from a current study using interviews and classroom observations. Teachers participated in interviews focusing on the their conception of the subject matter, the courses they were teaching, students in the class, and their individual approaches to transforming content knowledge. Findings suggest that a better understanding of these factors and the role they play in shaping curriculum would help teachers understand what they choose to teach, why they do it, and how it affects student education. Teacher education programs need to emphasize moral, social, political, and cultural dimensions of education. Teacher educators must provide prospective teachers with the skills and knowledge necessary to uncover the values embedded in pedagogical content knowledge. Since community and class background are such major influences in the classroom, it is important that teachers have a firm grasp on the socio-cultural factors on teaching and learning. (Contains 50 references.) (LH)