This child demonstrates classic features of obsessive-compulsive disorder (OCD): intrusive contamination fears (obsession) and repetitive handwashing behaviors (compulsion) performed to reduce anxiety. The symptoms are excessive, impairing school function, and persist beyond normal developmental concerns. According to MCCQE objectives, first-line treatment for mild to moderate pediatric OCD is cognitive-behavioral therapy (CBT) with exposure and response prevention (ERP). ERP involves gradual exposure to feared contaminants while preventing the compulsive handwashing response, thereby reducing anxiety through habituation and cognitive restructuring. Pharmacologic treatment with selective serotonin reuptake inhibitors (e.g., fluoxetine) is indicated for moderate to severe cases or when CBT alone is insufficient, but it is not the preferred initial intervention when psychotherapy is accessible. Risperidone is not first-line and may be considered only as augmentation in refractory cases. Changing schools or providing a teaching assistant does not address the underlying anxiety disorder. Early evidence-based intervention improves prognosis and functional outcomes in pediatric OCD.