A growing body of research documents the effectiveness of classroom management programs on a range of student outcomes, yet few early-career teachers receive training on these practices prior to entering the classroom. Moreover, few studies have attended to how variations in teacher distress or level of classroom misbehavior affects training benefits. This study reports findings from a randomized trial of a teacher training program that combined two evidence-based programs (Good Behavior Game [GBG] and MyTeachingPartnerTM [MTP]) to determine their impact on novice teachers and their students. In addition, the current study reports findings on moderated impacts by initial teacher distress as well as the overall classroom level of misbehavior. The sample included 188 early-career teachers (grades K-3) in their first three years of teaching from three large, urban school districts. Analyses indicated that intervention had no main effects, but yielded moderated impact depending on the combination of the baseline levels of classroom disruptive behavior and teacher distress; it appears that the program impacts were greatest in the highest risk circumstance (i.e., high teacher stress and elevated challenging student behaviors). For those classrooms, those assigned to intervention evidence improved behavior and student achievement compared to control counterparts by the spring of the training year, relative to the fall baseline (d = 0.18-0.70 depending on outcome). This study is significant in that it highlights effects during a critical window of training and coaching for early career teachers and the need to consider teacher and classroom contextual factors that may moderate professional development efforts. [This paper was published in "Journal of School Psychology" v78 p75-95 2020.]