Better integration of evidence-based practices (EBPs) in schools can improve access to effective youth mental health care. However, EBPs typically developed and tested within clinics may not be feasible for school-based implementation. We conducted a small randomized trial comparing Show Me FIRST, a brief intervention designed for efficient uptake in diverse clinical settings, against usual care (UC) in a school-based sample of 34 youth (70.59% female, 79.41% White; 11.76% Latinx; M = 12.21 years old; 41.18% received free or reduced lunch) with significantly elevated depression and anxiety. Using a mixed methods approach to gauge feasibility and efficacy, we found that school-based providers were able to deliver most content with fidelity and within six sessions. Youth and providers reported significant symptom improvements, but comparisons against UC were nonsignificant. Providers reported several challenges to implementing Show Me FIRST with the high-risk sample that may help explain these findings and suggest future adaptations.