Because financial, technical, and geographic constraints often limit the ability of health care providers to reach all children in need of care, especially in developing nations, some governments, donor agencies, and other development organizations are exploring the use of interagency collaboration to deliver health care services in schools. This paper examines the need for health and education agencies to work together to ensure that school-aged children have adequate health care. The paper identifies factors critical to the successful implementation of integrated and interagency programs, analyzes the organizational and institutional barriers to such collaborations, proposes ways to overcome such barriers, and provides a brief inventory of school-health programs undertaken in developing countries. The first part of the paper discusses the rising concern for school-aged children in developing countries regarding their health and nutrition, and the link between children's health and educational achievement. This part makes a case for interagency collaboration for school-based health programs, and examines elements of successful programs, barriers to such collaboration, and ways governments and schools can overcome the constraints. A table summarizes key strategies discussed in the section, objectives for the strategies, possible outcomes, and some implementation issues. The second part of the paper describes programs and activities targeting school-aged children, with a school-based health component, and currently in operation and involving interagency collaboration in developing nations. The following information is provided for each program: (1) project sponsor; (2) other participating organizations); (3) dates of operation; (4) interventions available; and (5) program strengths. (Contains a 39-item bibliography.) (KB)