This study explored the influence of a Saturday Science program that used explicit reflective instruction through contextualized and decontextualized guided and authentic inquiry on K-2 students' views of nature of science (NOS). The six-week program ran for 2.5 hours weekly and emphasized NOS in a variety of science content areas, culminating in an authentic inquiry designed and carried out by the K-2 students. The Views of Nature of Science Form D was used to interview K-2 students pre- and post-instruction. Copies of student work were retained for content analysis. Videotapes made of each week's science instruction were reviewed to ensure that explicit reflective NOS instruction took place. Explicit NOS teaching strategies included (1) introducing NOS through decontextualized activities, (2) embedding NOS into science content through contextualized activities, (3) using children's literature, (4) debriefings and embedded NOS assessments, and (5) guided and student-designed inquiries. Results indicate that K-2 students improved their NOS views over the course of the program, suggesting that they are developmentally ready for these concepts. Students developed adequate views of the distinction between observation and inference, the creative NOS, the tentative NOS, the empirical NOS, and to a lesser degree, the subjective NOS. (Contains 3 tables.)