Youth anxiety disorders are highly prevalent and are associated with considerable school impairment. Despite the identification of well-supported strategies for treating youth anxiety, research has yet to evaluate the differential effects of these treatments on anxiety-related school impairment. The present study leveraged data from the Child/Adolescent Anxiety Multimodal Study to examine differential treatment effects of CBT, sertraline, and their combination (COMB), relative to placebo (PBO), on anxiety-related school impairment among youth (N = 488). Latent growth modeling revealed that all three active treatments demonstrated superiority over PBO in reducing anxiety-related school impairment over time, with COMB showing the most robust effects. According to parent report, medication strategies may have stronger effects on anxiety-related school impairment among males than among females. Results were discrepant across parents and youth. Findings are discussed in terms of clinical implications for anxious youth and the need for continued research to examine treatment effects on anxiety-related school impairment.