The purpose of this study was to describe and analyze transition into elementary classrooms of students in a master of arts in teaching (MAT) program. Data sources included feedback, written observations and internship evaluations of students, informal conversations with mentoring teachers, and formal interviews with two mentors. One mentor worked with an intern who eased smoothly into the classroom, and the other mentor worked with two interns who experienced dissonance within the classroom culture. The mental frameworks of professional culture that MAT interns brought with them from previous experiences served to facilitate creative teaching as well as cause a disconnect between the MAT interns' expectations of and transition into the classroom. Mentor teachers expressed beliefs that MAT interns were more mature and committed to teaching than traditional interns and were consequently expected to take on responsibilities earlier in the internship. Implications for programs working with career switchers are discussed.