While some researchers have argued for science classrooms that embrace open-inquiry by engaging students in doing science as scientists do (cf. National Research Council [NRC] 1996; Driver et al. in Sci Educ 84:287–312, 2000; Windschitl et al. in Sci Educ 87(1):112–143, 2008), others have argued that open-inquiry is impractical, ineffective, and perhaps even counter-productive towards promoting normative scientific ideas (cf. Kirschner et al. in Educ Psychol 41(2):75–86, 2006; Settlage in J Sci Teach Educ 18:461–467, 2007). One of the challenges in informing the debate on this issue is the scarcity of well-documented courses that engage students in open-inquiry characteristic of scientific research. This paper describes the design, implementation, and outcomes of such a course for undergraduates planning on becoming elementary teachers. The goal of the class was to immerse future teachers in authentic, open-inquiry (without specific learning goals related to scientific concepts) in hopes that students would come away with a deeper understanding of the nature of science (NOS) and improved attitudes towards science. Data collected from a variety of sources indicate that an authentic, open-inquiry experience is feasible to implement in an undergraduate setting, gives students a more sophisticated NOS understanding, improves students' attitudes towards science and open-inquiry, and changes the way they intend to teach science in their future classrooms.