In 1876, St. Mary Parish became the second Catholic parish in Janesville as the capacity of St. Patrick Church was no longer able to hold the parishioners of the growing community. The church was built on the corner of Wisconsin and North First Streets (currently East Wall Street). As the population continued to swell, a new St. Mary Church was built on the site of the old building. This new church building was dedicated on June 14, 1902. In 1913, St. Mary School was established in the former church building which had been moved to the corner of Wisconsin Street and Prospect Avenue. Ninety-six students enrolled that first year in which education was offered for first through sixth grades. Two years later, seventh grade was added, followed by eighth grade the very next year. In 1921, ninth grade was added, along with plans to add a high school program once a new building was erected. An adjacent plot of land was purchased for the boys’ playground and for future growth. Substantial and sustained growth by 1919, made it necessary to convert the third floor of the school building, currently being used as the church hall, into additional classroom space.
In 1927 plans were developed to build a new school, and on May 12, 1929, the new school building located at 307 East Wall Street was dedicated. Kindergarten was added in 1930; however, it was abandoned in 1932 when General Motors moved its plant to Kansas City, MO. Enrollment at the school grew from 458 students in 1947 to its peak of 568 students in 1952! That year there were 74 students in grade one alone (all in one room)!
In 1949 the school playground was blacktopped, which was a welcome relief after twenty-two years of gravel. With classes averaging 50 students per grade by 1959, it was decided to renovate one-half of the auditorium into classroom space. Continued overcrowding finally forced St. Mary to eliminate ninth grade. By the 1970’s many Catholic schools faced declining enrollment and imminent closings. Despite its own declining enrollment, St. Mary Parish strongly supported maintaining our beautiful school and their support has been unwavering since. St. Mary School is now ninety-six years old, still going strong, and committed to excellent academics in a Catholic faith-filled environment.