A researcher-developed questionnaire regarding the importance and developmental appropriateness of 12 specific elements of the nature of science (Alshamrani, 2008) for early elementary (kindergarten through fourth grade [K-4]) science instruction was mailed to a random sample of U.S. K-4 teachers. At least half (N = 377) of the respondents reported introducing the inferential, empirical, creative, collaborative, tentative, and cultural aspects of the nature of science (NOS) during the current school year, as well as the idea that no single step-by-step scientific method exists. Over 90% of respondents identified the inferential, empirical, and creative aspects of the NOS as developmentally appropriate for the grade level taught. Based on a 5 point scale (0 = "not at all important and 4 = very important"), the mean scores of eight NOS elements were above a value of three, which corresponded with the descriptor somewhat important to include in K-4 science instruction: the inferential, empirical, creative, collaborative, cultural, and tentative NOS, along with the ideas that replication is an important aspect of experimental research and that no single stepwise scientific method exists. A series of binary logistic regression analyses were used to explore the impact of three predictor variables (developmental appropriateness, importance, and presence in state standards) on teachers' self-reported introduction of each of the NOS elements during the 2009-2010 school year. The data for the presence of the NOS elements in state standards were extracted from a previous study (McComas, Lee, & Sweeney, 2009). Developmental appropriateness was a significant predictor of teachers' introduction of the NOS element for all except the collaborative, empirical and inferential aspects of NOS. Importance was a significant predictor for all 12 NOS elements of interest. A NOS element's presence in the state standards significantly predicted teachers' introduction of that NOS element for only two aspects of NOS, the creative aspect of science and the idea that scientists do not all follow a universal scientific method. The implications of this study for science education are discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]