This study provides qualitative analysis of data that answers the following research question: how do college science faculty teach science and NOS and incorporate aspects of NOS and the history of science into their undergraduate courses? The study concentrates on four cases and more specifically on three introductory science classes and on four instructors who taught those courses. These instructors were chosen as case studies to explore in greater detail what occurs inside introductory science courses in one particular higher institution in the Northeastern United States. Participants' teaching styles are presented through a combined and detailed presentation of interview data and classroom observations supported with examples from their classroom activities. Constant comparative approach was used in the process of organizing and analyzing data. Findings revealed that participants preferred to use the traditional teacher-centered lecturing as their teaching style and their main concerns were to cover more content, develop the problem solving skills of their students, and teach the fundamental principles of their subjects without paying special importance to the NOS aspects. The study also revealed that other variables of teaching science, such as large class size, lack of management and organizational skills, teaching experience, and instructors' concerns for students' abilities and motivation are more important for these scientists then teaching for understanding of NOS.