This study examined the response of parents of elementary school-aged children to a school-based body mass index (BMI) screening and parent notification program conducted in one Minnesota school district in 2010-2011 and whether parent's response was moderated by child's weight status. Randomly selected parents (N = 122) of second- and fourth-grade students completed a mailed self-administered anonymous survey. Child's weight status was determined using measured height and weight. Most parents read the BMI notification letter and considered it helpful, independent of child's weight status. Parents of overweight children were significantly more likely than parents of normal weight children to report healthy lifestyle changes. This low-intensity intervention has the potential to support children, especially overweight children, and their parents to make healthy lifestyle changes. Future studies should investigate whether parent's response contributes to improved short- and long-term health outcomes for children.