DuPage County Health Department collected de-identified data from health forms submitted by participating schools for academic years 2011-2015 for kindergarten, sixth-, and ninth-grade students to determine the prevalence of obesity and elevated blood pressure among public school students. The prevalence of obesity in students for the 2014-2015 school year was 15.1%, and the prevalence of elevated blood pressure was 22.8%. Students in the "obese" body mass index percentile category had an elevated blood pressure prevalence of 44.2%, which was higher than students in the "nonobese" category (P < .001). Significant differences were also observed both by sex and by grade. The results identify the need to support implementation and evaluation of policies to reduce childhood obesity and improve health outcomes. By partnering with schools to obtain preexisting health data, state or local health departments with limited resources may replicate these methods to develop a childhood obesity surveillance system.