For the past two decades there has been increasing emphasis on argumentation in school science. In 2007, the National Research Council published a synthesis report that emphasizes the centrality of constructing, evaluating, and using scientific explanations. Participating in argumentation is seen as fundamental to children's science learning experiences. These new expectations increase challenges for elementary teachers since their understanding of and experiences with science are overwhelmingly inconsistent with teaching science as argument. These challenges are further amplified when dealing with prospective elementary teachers.

The current study was guided by the following research questions: (1) What are the ways in which preservice elementary teachers appropriate components of "teaching science as argument" during their student teaching experience? (2) To what extent do components from prospective elementary teachers' reflections influence planning for science teaching? (3) What elements from the context influence preservice elementary teachers' attention to teaching science as argument? This study followed a multi-participant case study approach and analyses were informed by grounded theory. Three participants were selected from a larger cohort of prospective elementary teachers enrolled in an innovative Elementary Professional Development School (PDS) partnership at a large Northeast University. Cross-case analysis allowed for the development of five key assertions: (1) The presence of opportunities for interacting with phenomena and collecting first hand data helped participants increase their emphasis on evidence-based explanations. (2) Participants viewed science talks as an essential mechanism for engaging students in the construction of evidence-based explanations and as being fundamental to meaning-making. (3) Participants demonstrated attention to scientific subject matter during instruction rather than merely focusing on activities and/or inquiry processes. (4) Scaffolded protocols positively influenced participants' attention to having students construct evidence-based explanations during science planning and teaching. (5) Teachers' beliefs about children's science capabilities influence their attention to and adoption of practices associated with teaching science as argument. Findings are discussed in terms of their implications for teacher education, such as the use of coherent conceptual frameworks to guide coursework and field experiences and the development of video-based cases that represent "images of the possible" associated with challenging reform-oriented teaching practices.