This study investigated contextual changes in perceptions of science teaching self-efficacy through pre-, post- and retrospective administrations of the Science Teaching Expectancy Belief Instrument (STEBI-B) among preservice elementary teachers when exposed to a science teaching methods course. Findings revealed that the number of postsecondary science courses completed, and prior school science experiences had a significant main effect on personal science teaching efficacy (PSTE) but not science teaching outcome expectancy (STOE). There was no evidence for significant interaction effects between variables on both efficacy subscales. The implications of this study relate to organization, structure, and dynamics of elementary science teacher preparation.