One hundred fifty-four fourth graders took part in an investigation of the Open Circle Program (OCP), an intervention model that encourages students, teachers and administrators to learn and practice communication, self-control and social problem-solving skills. Eight classrooms, two in each of four schools, were sampled. Two of these schools were located in middle to upper-middle class suburban areas and two served more diverse populations. Half the classrooms were headed by teachers well versed in OCP curriculum. The other half was not implementing a social competence program. Participants completed the student version of the Social Skills Rating System (SSRS) once in the fall and again in the spring. Teachers also rated the social competence of students at these same two points in the school year. Doubly-repeated measures mixed-design MANOVA analyses revealed that across the school year, OCP participants showed significantly greater teacher-reported improvements in both social skills and problem behaviors than did control group members. Although the largest gains were made by OCP children in urban areas, significant positive effects of program participation were shown by all students, regardless of school setting.