Science teaching and teacher education in the U.S.A. have been of great national interest recently due to a severe shortage of science (and mathematics) teachers who do not hold strong qualifications in their fields of study. Unfortunately we lack a rigorous research base that helps inform solid practices about various models or elements of teacher preparation (Allen, 2003; Futrell, 2010; Sykes, Bird, & Kennedy, 2010; Wang, Odell, Klecka, Spalding & Lin, 2010). In reviewing research on science teacher education, Anderson and Mitchener (1994) found that "there is only a small amount of research on pre-service education and what does exist is rather limited in scope and usefulness" (p. 28). A broader review of 37 studies in teacher preparation in general conducted for the U.S. Department of Education (Wilson, Floden, & Ferrini-Mundy, 2001) concluded that "there is no research that directly assesses what teachers learn in their pedagogical preparation or that evaluates the relationship of pedagogical knowledge to student learning or teacher behavior" (p. 12). There have not been enough studies completed of sufficient quality in teacher preparation - in any subject matter area--to provide a confident sense of "what works" and "why it works" (Allen, 2003). Many studies in teacher preparation are case studies or very limited sample size investigations which make generalizations to theory applicable only to these samples, and comparisons among similar populations or programs very problematic (for a more comprehensive review, refer to the "Handbook of Research on Science Education" edited by Abell & Lederman, 2007).