Modular therapies are systematic approaches to mental health treatment based on therapeutic elements common to multiple evidence-based practices. Given the flexibility and efficacy demonstrated in outpatient settings, modular therapies may be a feasible and effective approach to mental health treatment in schools. We conducted a systematic literature review to summarize the current evidence regarding modular school mental health programs, which consisted of seven studies investigating four distinct school-based modular treatment packages for internalizing concerns. In our review, no studies specifically examined modular therapy for disruptive behavior disorders--a common referral question for school mental health practitioners. Overall, the modular approach appears to be acceptable to stakeholders, but it is unclear whether school-based clinicians can implement proposed modules with adequate integrity, which limits the conclusions that can be drawn regarding real-world effectiveness. We believe implementation studies are needed to draw firm conclusions regarding the feasibility and effectiveness of modular school mental health, but the research to date appears promising.