St. Mary's School is a historic Roman Catholic school building in Wilmington, New Castle County, Delaware. It was built in 1866 to serve children of parishioners of the adjacent St. Mary of the Immaculate Conception Church. It housed a parochial school until 1979, after which it was occupied by the Elementary Workshop Montessori Schooluntill 2014 Then it housed Pine Street Learning Academy a Pre-School and Early Childhood Education Center. It is a three-story, five bay by four bay, brick structure with a low hipped roof in the Italianate style. It features a wooden box cornice around the entire roof line. It added to the National Register of Historic Places in 1983. References External links Elementary Workshop Montessori School website School buildings on the National Register of Historic Places in Delaware Irish-American culture in Delaware Italianate architecture in Delaware School buildings completed in 1866 Schools in Wilmington, Delaware Defunct schools in Delaware 1866 establishments in Delaware National Register of Historic Places in Wilmington, Delaware