School-based health centers (SBHCs) provide physical and mental health services on school campuses to improve student health status, and thereby potentially facilitate student academic success. With a growing emphasis on school accountability and the simultaneous dwindling of resources at the federal, state, and local levels, SBHCs face increasing pressures from school administrators and funders to document their impact on student academic achievement. This article reviews the methods, findings, and limitations of studies that have examined the relationship between SBHCs and academic performance. It also describes methodological challenges of conducting and interpreting such research, and discusses factors and intermediate variables that influence student academic performance. Recommendations are offered for SBHC researchers, evaluators, and service providers in response to the pressure they are facing to document the effect of SBHC services on academic outcomes.