Background: School-based dental programs target high-risk communities and reduce barriers to obtaining dental services by delivering care to students in their schools. We describe the evaluation of a school-based dental program operating in Chelsea, a city north of Boston, with a low-income and largely minority population, by comparing participants' oral health to a Massachusetts oral health assessment. Methods: Standardized dental screenings were conducted for students in kindergarten, third, and sixth grades. Outcomes were compared in bivariate analysis, stratified by grade and income levels. Results: A greater percentage of Chelsea students had untreated decay and severe treatment need than students statewide. Yet, fewer Chelsea third graders had severe treatment need, and more had dental sealants. There was no significant difference in the percentage of Chelsea students having severe treatment need or dental sealants by income level. Conclusions: Students participating in our program do not have lower decay levels than students statewide. However, they do have lower levels of severe treatment need, likely due to treatment referrals. Our results confirm that school-based prevention programs can lead to increased prevalence of dental sealants among high-risk populations. Results provide support for the establishment of full-service school-based programs in similar communities.