BEACHES assesses the social and environmental factors that may influence children's physical activity and sedentary behaviors in various settings. Environmental variables include the child's location, people that are present, whether the child is prompted for physical activity or sedentary behavior, and whether or not the child views media and ingests food. The physical activity codes have been validated using heart rate monitors and accelerometers, and the system can be used in homes, schools, and most settings where children might be found.