This study will examine the potential effects of regulating the sale of competitive foods and beverages in schools, a lever which policy-makers may use to positively influence children’s consumption behaviors to reduce the prevalence of obesity among children. The Healthy, Hunger-Free Kids Act of 2010 provides the U.S. Department of Agriculture (USDA) with increased capacity to regulate in this area, making this a timely study. The principal research question is: To what extent do school competitive food and beverage practices affect adolescent weight? The study will target youth who were in the 8th grade in 2007, using secondary data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K), a nationally representative survey of children. Investigators will examine effects of competitive food and beverage practices and food/beverage purchasing at school on adolescent weight, including potential differential effects for lower-income and minority youth. Borrowing from the education literature, value-added models will be used to estimate the effects of competitive food and beverage practices on adolescent body mass index (BMI) and the probability of obesity. Value-added models will be used to attempt to disentangle the effects of competitive food and beverage practices from unobserved factors that may also affect weight using earlier measures of BMI as controls.