Science lessons using inquiry only or history of science with inquiry were used for explicit reflective nature of science instruction for second-, third-, and fourth-grade students randomly assigned to receive one of the treatments. Students in both groups improved in their understanding of creative NOS, tentative NOS, empirical NOS, and subjective NOS as measured using VNOS-D as pre- and post-test surveys. Social and cultural context of science was not accessible for the students. Students in second, third, and fourth grades were (...) able to attain adequate views of empirical NOS, the role of observation and inference, creative and imaginative NOS, and subjective NOS. Students were not able to express adequate views of socially and culturally embedded NOS. Most gains in NOS eroded by the next school year, except for tentative NOS for both groups and creative NOS for the inquiry group. (shrink)