St. Mary on the Hill Catholic School St. Mary on the Hill Catholic School, a K-8 private school and the parish school of St. Mary on the Hill Catholic Church. SMCS serves families from Richmond and Columbia Counties in Georgia and Aiken County in South Carolina. We welcome families of all faiths. Accredited by AdvancED, SMCS combines a challenging curriculum with a caring and supportive environment to nurture our students'' academic success and spiritual growth. We look forward to meeting you!