This case study focused on a preservice teachers' (Morgan) efforts to explicitly emphasize nature of science (NOS) elements in her first-grade internship classroom. The study assessed the change in first grade students' views of the inferential, tentative, and creative NOS as a result of the explicit instruction. Morgan held appropriate views of NOS, had the intention and motivation to teach NOS, and had a supporting experience explicitly emphasizing NOS embedded in physics content to peer college students. Data sources included weekly classroom observations of explicit NOS science lessons taught by Morgan, interview of Morgan to determine that her views of NOS were informed and that she would have the NOS content knowledge to teach in line with recommended reforms, and interviews of the first-grade students pre- and postinstruction to determine the influence of Morgan's instruction on their views of observation and inference, the tentative NOS, and the creative and imaginative NOS. Data were analyzed to determine (a) the approaches Morgan used to emphasize NOS in her instruction, and (b) students' views of NOS pre- and postinstruction to track change in their views. It was found that Morgan was able to explicitly emphasize NOS using three teacher-designed methods, and that the influence on student views of the inferential, tentative, and creative NOS was positive. Implications for teacher development are provided. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 43: 377–394, 2006