In this study, we (a) describe patterns of challenging student behaviors (classwide and for a target student with attention deficit hyperactivity disorder [ADHD]) and teacher behaviors (i.e., praise, commands, and responses to challenging behavior) in kindergarten through Grade 5 classrooms, (b) examine the relations between these behaviors, and (c) describe a threshold of teacher behaviors most associated with low levels of challenging student behavior. Participants were 55 teachers observed using a modified version of the Student Behavior Teacher Response (SBTR) system. Across grades, there was variability in rates of classwide challenging behavior per hour (M = 35.81 to 102.62) and rates of praise per hour (M = 10.90 to 37.70). The percentage of challenging behaviors to which teachers responded appropriately was generally low (M = 27% to 47%) and stable across grades. For classwide challenging behavior, higher percentages of appropriate teacher response were significantly associated with lower rates of challenging behavior (b = -0.43; p < 0.01), but effective commands and labeled praise were not. Classwide challenging behaviors dropped to 30 per hour once teachers reach a threshold of 51% appropriate response, with little incremental benefit at higher levels. Implications for professional development and future study of behavior management practices are discussed.