Sunday Masses were held in the basement of Holy Trinity until the new St. Mary’s Church, school and convent were built and dedicated on February 2, 1923. At that time, there were 300 families and 1300 members. The Sisters of Christian Charity staffed the school from 1923 until 1987. The Church and school served the parish nearly 45 years, until Sunday Masses were to crowded and the school needed more space.
A building committee was formed in 1968 to begin plans for a new church. Pastors of the parish over the years had purchased the old rectory, land for a new church, paid off the parish debt and started a building fund. St. Mary’s School joined the Central Catholic School system incorporated in 1969.
On December 8, 1970, the new Church of St. Mary was dedicated at a corner-laying ceremony. On January 19, 1971, with the celebration of Masses, the new church was officially opened. At this time, there were over 700 families and 2500 members. In 1983, St. Mary’s School joined the New Ulm Area Catholic Schools (NUACS). In 1988, the former convent was remodeled and became Educare, a combination pre-school and day care.
In 1999, St. Mary’s School saw the last of its students move to the new St. Anthony Elementary School building.