St. Mary's Springs High School is a private Catholic, coeducational, college preparatory high school owned by the Archdiocese of Milwaukee.  It was founded by the Sisters of St. Agnes in 1909.

Enrollment is open to all qualified students regardless of their religious affiliation.

St. Mary's Springs High School is accredited by the North Central Association of Colleges and Secondary Schools, and is a member of the Wisconsin Association of Non-Public Schools.

St. Mary's Springs history is long and proud.  The Sisters of Saint Agnes came to the present site of the school in 1901 to open a sanitarium.  The first building built on the site, Boyle Hall, was constructed in 1901. Boyle Hall was torn down in the winter of 2005 due to its deterioration.  It was used as a sanitarium, along with St. Agnes Hall until 1909 when it was converted into a boarding school for girls. The first graduation was held in 1911.  The school, though run by the Sisters of St. Agnes, became affiliated with Catholic University of America in 1915 and then became known as St. Mary's Springs Academy.  The old Administration Building was constructed in 1928 and is currently not in use.  These added facilities allowed the Sisters to respond to Archbishop Stritch's concern for Catholic education for high school aged boys.  In 1939, St. Mary's Springs Academy revised its mission and opened its doors to young men.  In 1956, boarding facilities were discontinued. 

With increasing enrollment during the 1950's and 60's, a need arose for another building.  Many in Fond du Lac still remember the telethons that the school held to raise money for this new building, and others still have the footballs signed by Ray Nitschke during these telethons!  In 1970, the school became jointly sponsored by the Archdiocese of Milwaukee as well as the Congregation of St. Agnes.  In the same year, the school's name was changed to St. Mary's Springs High School.  Sponsorship of the school by the Congregation of St. Agnes ended in 1985, but sisters continue to teach in the school today.

St. Mary's Springs High School is located on the eastern edge of the City of Fond du Lac and is situated on the Niagara Escarpment, known locally as "the ledge".  The Ledge, a geologically significant ridge that overlooks Fond du Lac and nearby Lake Winnebago, stretches over 1,000 miles from the Great Lakes to Niagara Falls.  The school's location on the Ledge affords the campus with a beautiful setting.