On September 23, 1873, Mother Emelie, American provincial of the Sisters of St. Mary of Namur, Lockport, New York, accompanied by Sister Mary Angela and Sister Stanislaus, arrived in Waco at the urging of Bishop Claude Marie Dubuis, the second bishop of Galveston, for the purpose of opening a Catholic school. On October 1, 1873, in a residence on the southwest corner of Sixth and Washington the school opened, and one pupil, Thomas Bloomer, a Catholic, enrolled. The third day, six more students, faith undisclosed, enrolled. Subsequent to that, the enrollment grew steadily.
On June 12, 1874, Sister Angela bought a lot on the northwest corner of Eighth and Washington, later the site of the M Bank Building. The date of purchase was the feast of the Sacred Heart, so the school was named Academy of the Sacred Heart. The first brick was laid on July 15, 1874. The academy, in its red-brick Victorian buildings surrounded by magnolia trees, was enclosed by a typical period-style iron-post fence. In November 1873 Mother Emelie returned to New York, and Sister Angela remained as superior of the academy for many years. She is said to have fought carpetbaggers, ignorance, and anti-Catholicism to bring the school to popularity and academic excellence. The school eventually came to be accredited by both the Catholic University of America and the University of Texas.
From 1873 to 1946 the boarding and day school provided grades one through twelve to boys and girls. Boys attended through grammar school only, and none were boarding students. The first graduating class (1881) was four girls. The academy was a popular boarding school for girls whose families lived on surrounding farms. Growth in enrollment and plans to build a new school encouraged the sisters to purchase two tracts of land in northwest Waco. Plans to relocate and enlarge never materialized, however. In 1946 the nuns, probably because of declining student enrollment, a decline in religious vocations from the students, and an emerging interest in parochial rather than private schools in Waco, closed the Academy of the Sacred Heart. The sisters donated twenty-three acres they had purchased for expansion to the Diocese of Galveston in 1941. St. Louis School and Reicher High School were later opened at that site.