Background: Curtailing childhood obesity is a public health imperative. Although multicomponent school-based programs reduce obesity among children, less is known about the implementation fidelity of these interventions. This study examines process evaluation findings for the Healthy, Energetic Ready, Outstanding, Enthusiastic, Schools (HEROES) Initiative, a tri-state school-based childhood obesity prevention intervention based on the coordinated school health (CSH) model. Methods: Site visits were conducted that included key stakeholder interviews, observation, and document review. Scores were given for 8 domains, and a total implementation score was calculated. Two-way analyses of variance were conducted to examine the relationship of 4 school-level characteristics: elementary vs. middle/high schools, public vs. private schools, district vs. building level implementation, and socioeconomic status on each implementation area. Results: Overall, schools had high fidelity scores, although some domains were implemented more successfully than others. Three school-level characteristics were associated with 1 or more domains, with elementary schools and schools implementing at the building level consistently having higher implementation scores than their counterparts. Conclusions: Process evaluation findings provide insight into successes and challenges schools implementing the CSH approach may encounter. Although preliminary, these findings on school-level characteristics establish a new area of research related to school-based childhood obesity prevention programs' implementation fidelity.