This study explored changes in preservice teachers’ nature of science pedagogical views and nature of science rationales using pre- and post-course written responses as well as interview data. Through systematic analysis, themes were generated and compared to the NOS literature. Comparisons between pre- and post-course data demonstrate improved and deepened NOS views, NOSP views that are more aligned with NOS literature, and a greater number of rationales for including NOS. All participants were enrolled in the “Inquiry and Natures of Science, (...) Technology, and Engineering” course. However, six participants were enrolled in INSTE as their first course in which NOS and NOSP were addressed. The other six participants were enrolled in INSTE as their second course in which NOS and NOSP were addressed, with science methods as their first course in which NOS and NOSP were addressed. By comparing participants enrolled in INSTE as their first course to those enrolled in INSTE as their second course, we observed that NOS understanding seemed to develop in a first experience alongside some NOS rationales, but NOSP views lagged for participants in INSTE as their first course. Participants enrolled in INSTE as their second course developed more robust and literature-aligned NOSP views and more multifaceted NOS rationales. Therefore, this study bolsters arguments that teachers need to receive extended NOS and NOSP instruction. (shrink)