The purpose of this study was to describe how six preservice science teachers learn to teach over a year and explain their learning by documenting their field experiences, teacher education courses, and their changing beliefs and practices. The findings reveal that teaching practices were strongly influenced by the cooperating teachers. Initially, all six interns attempted to mimic the lessons they witnessed their cooperating teachers teach. Later, the interns independently implemented instruction that emphasized key instructional or relational strategies as the cooperating teachers, regardless of whether or not they were experiencing success.