In 1919, Burlington, because of its crowded school conditions, needed a new high school.  At the same time, St. Mary's pastor, Fr. Van Treeck, discovered that nearly half of the Burlington public school system was Catholic--an opportune time to start a Catholic high school in Burlington. He held several parish meetings to present his plans.  Though small in number, the opposition was vehement and persuasive.  Archbishop Messmer would not give the necessary permission. Fr. Van Treeck did not give up.  He had his eye on the old St. Sebastian's Church then owned and used as a meeting hall by the St. Eustachius Benevolent Society.  The Society staunchly supported his plan and offered the hall. Father made arrangements with the School Sisters of Notre Dame for two teachers and ordered desks, books and other equipment. Father could only get one teacher.  So he opened St. Mary's High School as a two year commercial course school with an opportunity for the second year student to take sophomore subjects in English, Latin and Math. The set-up was indeed strange.  None of the equipment had arrived.

(In the hectic days of reconstruction after W.W. I, it was difficult to get.)  There was an old chunk-burning stove, one rickety cardtable, a three-legged chair, reed organ and stool.  Fortunately most of the textbooks had arrived. The high school was a doomed project--no equipment, very few students, little backing.  But then God sent Sister Michael. A person of fainter spirit and less faith would certainly have bolted for the door that first morning.  The condition were practically impossible. "We are quite as poor as the Savior, having barely a roof over our heads," she said.  With a true missionary spirit this undaunted nun, who had previously taught in the best schools in her Order, set about making a school out of nothing. In 1925, St. Mary's High School graduated its first class:  Florence Bieneman, Loraine Heck, Marie Rueter, and Raymond D. Bieneman. In 1926, they moved to a new building.  There was steady enrollment from then on, peaking at more than 350 in the late '60's. In 1970 they built a new gym and in 1993, the Marian Activity Center, with the addition in the fall of 1995 of the second floor of the MAC which houses a weight room and state-of-the-art computer lab.