The preparation of elementary teachers to successfully teach science in their classrooms is a central issue in science education. The teacher preparation program at a large Midwestern university was modified to include a new science content course aimed at this need. A pre-/postassessment research model involved participants (N = 154) completing a modified Science Teaching Efficacy Belief Instrument for preservice teachers, or STEBI-B (R. E. Bleicher, 2004; L. G. Enochs & I. M. Riggs, 1990) at the beginning and end of the semester-long course. Findings between pre-and postassessments include statistically significant increases in both subscales (Science Teaching Outcome Expectancy; Personal Science Teaching Efficacy Beliefs) in the STEBI-B instrument (alpha = 0.05). Implications include the role of an undergraduate science content course specifically designed for preservice elementary teachers, as well as recommendations for improvements and collaboration among faculty in education and natural sciences.