In this study, the psychometric properties of the Classroom Observation of Engagement, Disrespectful and Disruptive Behavior (COEDD), a systematic direct observation coding protocol designed to assess common school-based behavioral targets, were examined. Interobserver agreement and criterion-related validity were evaluated in a sample of 155 kindergarten- through third-grade students. Interobserver agreement was high across categories and criterion-related validity was supported by correlations between the COEDD categories and teacher ratings of student behavior on well-established teacher rating scales. Together these findings support continued study of the COEDD as a tool for quantifying student classroom behavior. Impact Statement This paper addresses the dearth of psychometrically sound behavioral observational methods in school settings. In this study, preliminary psychometric properties of the Classroom Observation of Engagement, Disrespectful and Disruptive Behavior (COEDD), a systematic direct observation coding protocol designed to assess common school-based behavioral targets that are critical to student success, were assessed. Results explore the validity and reliability of the instrument, as well as its capacity to capture meaningful, usable data for school-based assessment of children.