Many researchers and educators regard classroom-wide behavior management systems as an effective and efficient strategy to manage student behavior. This study evaluated the effectiveness of a classroom-wide management system called the Clocklight Program. Central to the program was a modified clock which was operated by the teacher by means of a hand held remote control. When the entire class was in compliance to behaviorally defined rules, the clocklight accrued time. If any student in the class was not compliant, the remote was used to shut off the clocklight. The entire class was rewarded when the clock reached the pre-specified amount of time. Participating were 24 second graders in a heterogeneous class in a rural southeastern Idaho public elementary school. Target student behaviors related to following instructions, appropriate seating, getting the teacher's attention, and giving corrective feedback. Baseline data were collected for 3 days, after which the program was implemented with the following instructional steps: (1) present reinforcers; (2) present target behaviors; (3) show students how to access rewards with the clocklight; and (4) deliver rewards. The results indicated that during the baseline period, the class was in compliance 111 minutes, or 43 percent of the instructional time. Following the baseline, the first group goal was 135 minutes and the class spent 202 minutes in compliance, 79 percent of total time available. During the next 3 days of the study, the class achieved its goal of time in compliance. The classroom teacher and the students evaluated the program positively. (KB)