A program was implemented in an elementary school to improve students' social skills, thereby reducing physically and verbally aggressive behavior and reducing off-task behavior. The targeted population consisted of second, third, and sixth graders in two northern Illinois elementary schools, one situated in a low socioeconomic neighborhood, the other located in a middle class neighborhood in an urban community. The behavioral problems were documented through teacher and student surveys, teacher anecdotal records, and behavioral observation checklists. A review of solution strategies suggested by educational literature, combined with an analysis of the problem setting, resulted in the selection of the following three major categories of intervention: instruction in cooperative problem solving; instruction in conflict resolution; and implementation of a cross-age mentoring-tutoring program. Post-intervention analyses indicated that the intervention improved student behavior. Many students were positively influenced by the strategies, and their social skills improved. Students with severe learning and behavior problems or dysfunctional families were less influenced by this type of intervention than students who were less troubled. (Appendices include copies of the teacher survey, student survey, observation checklist, observer instructions, and lesson plans and ideas. Contains 34 references.) (Author/AA)