This study built on prior research regarding the effectiveness of the National Center for Research in Early Childhood Education (NCRECE) course by exploring the individual course components. Core aspects of course engagement and performance were described and examined in relation to improvements in the observed quality of teacher-child interactions. Teacher characteristics were also examined as predictors of course engagement and performance. A sample of 150 preschool teachers participated in a semester-long, credit-bearing, college course designed to improve the quality of their emotional, organizational, and instructional interactions with children. Teachers' participation and performance in the course were high on average. Teachers' skill level in accurately and specifically explaining other teachers' instances of effective teacher-child interactions was related to improvements in their own observed teacher-child interactions. Finally, teachers with an early childhood major and those endorsing child-centered beliefs displayed better skills in detecting other teachers' high-quality interactions with children. Results are discussed in relation to designing more effective early childhood professional development programs. (author abstract)