MICDS (Mary Institute and Saint Louis Country Day School) is an American secular, co-educational, independent school with approximately 1,250 students from junior kindergarten through grade 12. Its 110-acre (45ha) campus is located in the St. Louis, Missouri, suburb of Ladue.
Each of the school's three divisions operate somewhat independently as a "school within a school". The Lower School, also referred to as The Ronald S. Beasley School, or "Beasley" for short, is for students in junior kindergarten through grade 4. The MICDS Middle School, grades 5 to 8, is in the former Mary Institute facilities. The Upper School on the former Country Day School campus serves grades 9 through 12.
A sister school for girls, Mary Institute, was founded in 1859 and was named for Eliot's late daughter Mary Rhodes Eliot, who had died at 17. In its early years, Mary Institute moved twice within the city of St. Louis; its third building, at the corner of Lake and Waterman, is now New City School.
In 1866, musical educator Kate J. Brainard became a lead professor at the Mary Institute and trained hundreds of girls. Smith Academy closed in June 1917, in part due to the proliferation of private elementary schools and public secondary schools in the area. Three months later, St. Louis Country Day School opened in northwestern St. Louis County. Inspired by the Country Day School movement nationally, it was not related to Smith, although a number of former Smith students enrolled that first year. St. Louis Country Day School's campus was in a bucolic setting reached by electric streetcar, far removed from the noise and grit of the city.
Mary Institute moved to its Ladue campus in 1931 and became independent of Washington University in 1949. The Mary Institute building contains a three-figure bronze sculpture by Cyrus Dallin: Alma Mater, honoring schoolmaster Edmund Hamilton Sears and donated by Eliza Northrop McMillan. By the 1950s, the tranquility of the Country Day campus was disrupted by the growth of the adjacent Lambert–Saint Louis International Airport. St. Louis Country Day School moved to a new campus next to Mary Institute in Ladue in 1958, and eventually sold its old campus to the airport. Eliot's grandson, Nobel Prize laureate T. S. Eliot, who attended Mary Institute's kindergarten and Smith Academy, spoke at Mary Institute's centennial in 1959.
In the 1970s, Mary Institute and Country Day began expanding their long-existing connections, including theatrical cooperation, into academic coordination. This would culminate in the schools' 1992 merger.
St. Louis Country Day headmaster John Johnson, who coordinated the merger, became head of the combined schools. The school observed its sesquicentennial during a celebration that ran from May 11, 2009, to May 11, 2010.
The school has one of the few high school cycling teams in St. Louis. They competed in the Tour De St. Louis in 2009; two MICDS riders finished with the peloton.
MICDS has an athletic rivalry with the nearby John Burroughs School. MICDS observes its Homecoming on the weekend when all the teams play Burroughs; there is a traditional bonfire and pep rally to inspire team spirit. MICDS also has a cross-state rivalry with The Pembroke Hill School in Kansas City.
↑"Meet Our Head of School". Mary Institute and Saint Louis Country Day School. Archived from the original on December 5, 2025. Retrieved November 12, 2025.
1234"Micds". Search for Private Schools. National Center for Education Statistics. Archived from the original on October 25, 2021. Retrieved November 12, 2025.
