This study describes the development, implementation, and evaluation of a structured physical activity intervention designed for high school students (years 11 and 12). A sample of 78 students was randomly allocated to control or intervention conditions for a period of ten weeks. Students in the control group (n = 40) participated in unstructured physical activity in a health and fitness center. Students in the intervention group (n = 38) participated in a ten-week structured health and exerc...