In 2006, the Anchorage School District implemented a school wellness policy to address the problem of obesity among its elementary-aged students. We assessed whether the addition of this policy is effective in protecting or preventing students from becoming overweight/obese over time. The methods involved following two cohorts of students for 5 years, a cohort not exposed and a cohort exposed to the policy. The results show that exposure to the policy does not significantly protect or prevent students from becoming overweight/obese. However, we found that regardless of being exposed to the policy, boys (odds ratio [OR] = 1.12), ethnic minorities, (OR = 1.18), and students from low socioeconomic backgrounds (OR = 1.44) were more likely to remain or become overweight/obese. Our findings suggest that factors outside the school may be impacting students' overweight/obese status. Efforts to curb the problem of childhood obesity should extend to the children's communities and homes.