This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the…

The high rates of dropping out and other engagement problems are significant concerns in the delivery of mental health and adjunct services to the families of at-risk children. Consequently, researchers have examined the correlates of attrition and have developed interventions to increase engagement and retention. However, the lack of a clear…

This paper briefly outlines current problems associated with chronic diseases in children and youth and provides indications for the types of future research and analysis needed to facilitate the development of solutions. In general, these problems are associated with the following: malignancies, hereditary anemias, cystic fibrosis, other chronic…

Notes the omission of a historical perspective in the research papers in this special issue on prosocial and aggressive play. Maintains that the past several hundred years can be characterized as a time of domesticating children's play, and that more research on rough-and-tumble play is needed. (LB)

This article discusses the successes of behavior analysts in affecting challenging behaviors in persons with developmental disabilities. Three future issues are then addressed: the development of challenging behaviors, the role of rule-governance in challenging behavior, and the behavior of persons who directly apply functional assessment and…

This paper examines the selection and influence of friends in schools which differ in the degree of "openness" in the instructional program. Data collected from over 4,000 students in grades 5, 6, 8, and 11 in 1973 and 1974 provide information on student characteristics, school structure and processes, and academic and affective outcomes for…