One broad research question researchers continue to pursue is: to what degree does science teacher education influence the thinking of preservice science teachers? In other words, how has the thinking of preservice science teachers changed during the course of teacher education? Different models of cognition suggest different foci for this research, leading to research on preservice science teachers' beliefs, knowledge, and pedagogical content knowledge, among other mental constructs. This study explores the question of preservice science teachers' thinking using a goal-driven theory of cognition. From this theoretical perspective, a person's actions are attempts to satisfy one or more of the goals he or she holds. Applied to the study of preservice science teachers' thinking, goal-driven models of cognition suggest that an important outcome of teacher education is for preservice science teachers to develop goals reflective of their pedagogical training. The research question for this study is: to what extent do the goals of preservice science teachers align with the instructional practice emphasized in teacher education? Qualitative methods were used to study the goals of three science student teachers from a STEM teacher education program at a large state university in southwestern USA. Interviews were conducted at the beginning and the end of the student teaching semester, with student portfolio submissions providing evidence for triangulation. We present three main findings: First, preservice teachers adopt goals reflective of many, but not all, of the pedagogical strategies emphasized in teacher education. Second, the goals of student teachers remain in flux over the course of the semester, with students tending to disengage from goals during this time. Third, conflict may arise between pedagogical goals, with student teachers resolving these conflicts in ways that are both research based and less than ideal. Finally, we present implications for teacher educators and those who conduct research on STEM teacher education.