In the summer of 2012, families throughout the United States, especially in urban areas, were alerted on dozens of days that the air was unsafe for their children to breathe. Some cities experienced record numbers of “code orange” and “code red” smog alert days. With childhood obesity also hitting record levels, how are families to balance the benefits for children of outdoor play with the need to reduce their exposure to harmful air pollution? And should they have to? As children in our region, metropolitan Atlanta, head back to school in August each year, “bad air” days become a conundrum...