This study had two purposes: (1) to test the hypothesis that teacher candidates who faced challenges in student teaching had lower self-ratings on teacher dispositions than their counterparts who did not face challenges in student teaching, and (2) to develop an explanatory model to predict teacher candidates’ challenging experiences in student teaching. As the authors hypothesized, teacher candidates who successfully completed student teaching had significantly higher self-rating scores on dispositions than their counterparts who faced notable challenges. The findings from this study stand to advance our understanding of how dispositions relate to instructional practices and approaches.