This five-year application is concerned with preventing substance abuse, comorbid mental and behavioral disorders, and school failure. We will direct an integrated set of previously tested preventive first-grade interventions at two correlated and confirmed early antecedents: early aggressive, disruptive behavior and poor achievement. The interventions we propose to integrate and test are directed at improving: 1) teacher's classroom behavior management; 2) family/classroom partnerships regarding homework and discipline; and 3) teacher's instructional practices regarding academic subjects, particularly reading. The combined preventive and educational intervention strategy will be a single Whole Day (WD) first-grade classroom program, built on the empirically determined recognition of the interdependence of these risk factors across substance abuse and educational failure. As in our past Baltimore preventive trials, we propose to test the effectiveness of WD in a developmental epidemiological design in which children and teachers are randomly assigned to intervention and standard setting conditions (controls; SC). A special aspect of this proposal is that in the same design we propose laying a foundation for moving what we have learned into policy and practice. While following the first-grade children as far as the end of third grade, we will follow their first grade teachers over two subsequent cohorts of first graders, to test whether the support and training structure sustains high levels of WD practice. We will also test whether the support and training structure is successful in training non-WD teachers, as far as the trial results warrant. This prevention services aim will be augmented by an economic analysis of the costs and effectiveness of the WD program. The research on effectiveness combined with research on moving from effectiveness to practice should increase the efficiency of developing evidence-based programs faster and earlier in both the prevention and education fields.