Because schools materially influence both health and education, they substantially determine the future well-being and economic productivity of populations. Recent research suggests that healthier children learn better and that more educated adults are healthier. School health is a cross-disciplinary field of study and a fundamental strategy that can be used to improve both health and education outcomes. Modern school health programs include 10 interactive components: health education; physical education and physical activity; nutrition environment and services; health services; counseling, psychological, and social services; physical environment; social and emotional climate; family engagement; community involvement; and employee wellness. This review is written for both health and education audiences. It integrates recent research and developments in relationships among health, education, and economic outcomes; health and education systems; the school health program, its components, and their effectiveness; cross-disciplinary collaboration; local, state, national, and international infrastructures and strategies; implementation science; and relevant academic research, training, and service.