This research examines specific areas of confidence and concern as expressed by 40 American undergraduate early childhood students on a practicum (supervised field-based internships); if their beliefs changed over the course of their practicum, and if prior teaching experience had an impact on their confidence levels. Areas of confidence and concern were determined through questionnaires, reflections and interviews at three points in time during the semester. Findings indicate that students were more confident when arranging the physical environment and least confident in managing children's behaviour. Significant changes in understanding and interaction with children, planning and implementing activities and overall confidence were observed over time periods. Experienced students initially showed and maintained higher confidence levels than inexperienced students who were much less confident at the start of the practicum, but improved significantly. Interestingly, by the end of the semester, this latter group was as confident as more experienced students. Here the factors that affected confidence, the factors that boosted student confidence at different time periods and differences in confidence among students based on prior experience are discussed.