St. Mary's – St. Alphonsus Regional Catholic School, previously known as St. Mary's Academy, is a private Roman Catholic elementary and middle school in Glens Falls, New York, serving kindergarten through 8th grade. The main building was added to the National Register of Historic Places in 1984. Also known as SMSA, the school teaches children not only academic subjects, but teaches them about the Catholic Faith. SMSA is the oldest parochial school in the area. It once included a high school, but it was trimmed down to 8th grade.