The purpose of this study was to longitudinally examine the teaching efficacy of agricultural science student teachers throughout the student teaching experience. The population of interest for this study was all agricultural science student teachers at Texas A&M University. The accessible sample of the population was all student teachers during the Fall 2004 semester (n = 33). Using the Teachers’ Sense of Efficacy Scale instrument (Tschannen-Moran & Woolfolk Hoy, 2001), efficacy in student engagement, instructional strategies, and classroom management were measured: 1) the first day of the 4-week on-campus portion of the student teaching semester; 2) the last day of the 4-week on-campus block; 3) the middle of the 11-week student teaching experience; and 4) the final day of the student teaching experience. It was concluded that efficacy in student engagement and instructional strategies changed, while efficacy in classroom management did not. Overall teaching efficacy also changed. Student teachers had “Quite a Bit” of teaching efficacy at the beginning of the semester, which slightly increased four weeks later, then decreased to its lowest level at the middle of the 11-week student teaching experience, and then rebounded by the end of the experience.