This study examined the course and malleability of aggressive behavior from beginning elementary school through transition into middle school.
In a developmental epidemiologically defined population of 1,000 urban first graders, a 2-year classroom-based randomized preventive trial was aimed at reducing aggressive behavior, an antecedent of delinquency, violent behavior, and heavy drug use in adolescence and adulthood. Earlier the authors reported impact in first grade on teacher and peer ratings and on classroom observations. The current article reports on the course and on sixth- grade teacher ratings of aggressive behavior. Improvement was observed during transition times in first grade and in middle school among the males in the preventive intervention who were more aggressive in first grade. (publisher abstract modified)