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Better Education. Brighter Future.


Mercy High School

On November 11, 1945, His Excellency the Most Reverend John Joseph Glennon, STD, Archbishop of St. Louis, turned the first spade of earth on the site of Mercy High School in University City.  This was a memorable date because it began a journey of Archdiocesan secondary education that still continues today at the current Trinity Catholic High School.

From the time classes began at Mercy High School on September 4, 1948, through the opening of St. Thomas Aquinas High School in Florissant in 1954, to the beginning of Rosary High School in 1961, to the merge of Mercy and St. Thomas Aquinas in 1985 to form St. Thomas Aquinas-Mercy High School and the eventually formation of Trinity Catholic High School in 2003 as a result of the merge of Aquinas-Mercy and Rosary, the constant has been an affordable, quality, Catholic education.

The Sisters of Mercy officially took charge of Mercy High School in 1946 and Mercy High School became the first coeducational Archdiocesan high school in St. Louis. Beginning with 273 students, Mercy grew quickly and 497 students roamed the halls in 1950, 747 students were enrolled in 1952 and by 1956 there were 1,114 Mercy students. The peak enrollment reached 1,200 students in the late 1950s.

After a successful decade of the 1960s that included steady enrollment, academic and athletic successes and the construction of a stadium with a field house, the 1970s was a decade of change for Mercy. Declining enrollment began to plague the school in the late 1970s as tuition costs rose quickly. A local school board was formed to try to stem the problems but by the winter of 1984 the decision was made to merge Mercy High School with St. Thomas Aquinas in Florissant. After 37 years at 1000 Pennsylvania Ave. in University City, the rich history, the over 6,000 alums, the diverse culture and racial heritage, the strong traditions, several members of the talented faculty and staff and dozens and dozens of students linked bonds with those of St. Thomas Aquinas to form St. Thomas Aquinas-Mercy High School in the fall of 1985.

St. Thomas Aquinas High School

Prior to the merge with Mercy High School, St. Thomas Aquinas enjoyed 31 years of academic excellence and tradition of its own dating back to 1954 when Aquinas served ninth grade students only in the old Sacred Heart building in the heart of Florissant. Those students referred to their school as “the little red school house on Jefferson St.’’

After going through several names for two years, St. Thomas Aquinas was “officially’’ named for the patron of Catholic schools in 1956 and plans were underway for a permanent site for the school. The design for the first Catholic high school in North County was that of a campus plan with special function buildings located around a central plaza. On June 7, 1958 the late Cardinal Joseph Ritter laid the cornerstone for the new St. Thomas Aquinas High School. Students began attending school on the new campus on October 6, 1958.

St. Thomas Aquinas High School was staffed by the Sisters of St. Joseph of Carondelet. Since its inception, St. Thomas Aquinas offered a comprehensive curriculum to serve all students in the North County and the surrounding areas. In addition to academics, St. Thomas Aquinas provided activities and athletics to students who desired a well-rounded education. Numerous league, district, sectional and state championships were won by  Aquinas athletes and a competitor in the 1968 America’s Junior Miss Pageant was an  Aquinas student.

As at Mercy, Rosary, St. Thomas Aquinas and Trinity High Schools, religious formation was a key component of a St. Thomas Aquinas education. Masses, prayer services, days of recollection and on and off campus retreats were all a part of personal and spiritual development.

Enrollment at St. Thomas Aquinas grew steadily from 1954 through the late 1970s topping out at over 1,500 students. Student numbers were steady in the early to mid 1980s and in the fall of 1985 St. Thomas Aquinas High School transitioned to St. Thomas Aquinas-Mercy High School when Mercy students joined the campus in Florissant.

Rosary High School

While St. Thomas Aquinas was enjoying its success in Florissant, Rosary High School was the place where Catholic Values and Preparation for the Future Met for 43 years on the other side of North County.

Nestled on Redman Rd. in Spanish Lake, Rosary fostered spiritual, physical, social and moral growth while also promoting scholarship, creativity and personal initiative.

In 1961 the School Sisters of Notre Dame (SSND) began to provide a rich, faith-based education with just 196 students and 12 faculty members. Since that first year, well over 9,000 students graduated from Rosary High School with strong Catholic values and an excellent secondary education.

Throughout its history, Rosary remained a fully-accredited St. Louis Archdiocesan high school. In addition to its fine academic offerings, Rosary boasted as many as 31 extra-curricular activities each school year, including sports, clubs and organizations, a school newspaper, drama, yearbook, KRHS radio and more. Eight state championships were won in sports and numerous other conference and district titles were earned throughout the years. Several academic competitions were won as well.

Through it all, the commitment and dedication to the honor of Mary, the Most Holy Mother of Jesus, never wavered. An active Campus Ministry provided a variety of avenues for students and faculty to grow deeper in their faith and Christian Service to the community by Rosary students was consistently encouraged.

Since its humble beginning, Rosary High School quickly grew and developed into not only a quality place of learning but also a well-respected institution in North St. Louis County. Countless educators contributed to Rosary’s success but none more that Sr. Karl Mary Winkelmann, S.S.N.D. who was first a teacher and then a Principal at Rosary High School, the school that was Second To None in Catholic education in St. Louis.

St. Thomas Aquinas-Mercy High School

In the fall of 1985, St. Thomas Aquinas and Mercy High Schools merged to form St. Thomas Aquinas-Mercy High School on the campus of St. Thomas Aquinas in Florissant.

Over 1,000 students attended Aquinas-Mercy in 1985 and were served by the school’s first principal, Mr. Paul Frein, who had previously been principal of St. Thomas Aquinas.

The successes in and out of the classroom of its predecessor schools, Mercy and Aquinas continued at Aquinas-Mercy. The curriculum remained current and challenging and 14 athletic state championships were won by the Falcons – nine in boy’s soccer, one in girl’s soccer and four in cheerleading.

Support for the school by both Mercy and St. Thomas Aquinas alums made improvements such as a new meeting room, air-conditioning in the cafeteria and library and the construction of the new Alumni soccer/football stadium possible.

After 42 years in Catholic education, Paul Frein retired in the summer of 2000 and was succeeded as Principal of Aquinas-Mercy by George Pressey. George Pressey led Aquinas-Mercy until the summer of 2002 when 1969 St. Thomas Aquinas alum Kirk Boschert was announced as the school’s new Principal. Kirk Boschert served at Aquinas-Mercy for one year and then helped form the new Trinity Catholic High School that resulted from the merger of St. Thomas Aquinas-Mercy and Rosary High Schools.

Trinity Catholic High School

Founded in 2003 to continue the legacy of Archdiocesan academic excellence at Mercy, St. Thomas Aquinas, St. Thomas Aquinas-Mercy and Rosary High Schools, Trinity Catholic High School was led in its first years by former Rosary Principal Sr. Karl Mary Winkelmann, S.S.N.D., who served as Trinity Catholic's first President, and Kirk Boschert, who served as Trinity Catholic's first Principal. It quickly became known as the place Where Everyone Makes A Difference.

The goal at Trinity Catholic is to provide its young men and women the highest quality private, Christian-based education in a diverse atmosphere. The comprehensive, college-preparatory curriculum offers something for every level of student as they prepare for life after high school. Over 95% of Trinity Catholic students continue in post-secondary education. Advanced College Credit and Advanced Placement courses are offered for junior and senior students as well as challenging honors-level classes at all grade levels. Leveled courses benefit all students as does a full-time Learning Consultant, a daily Academic Lab period and the Bridges course for freshmen. The student to teacher ratio of 11 to 1 allows Trinity Catholic students the personal attention they deserve.

Trinity Catholic has a wireless campus and technology offerings including iPads for each student, four computer labs (including two iMac labs) and elective course offerings in Art, Web Page Design, Graphic Art, Media, Business, Family and Consumer Science, Band and Choir, Computer Science and Industrial Technology - including Robotics and Architectural Modeling.

Outside the classroom, Titans have the opportunity to compete in Interscholastic sports as well as in Cheerleading, Student Council, National Honor Society, Diversity Club, Youth in Government, Drama Club, the Titan Alumni Players, the school newspaper and yearbook just to name of few of the extra-curricular activities offered.

Just as Mercy, St. Thomas Aquinas, Rosary and St. Thomas Aquinas-Mercy before it, Trinity Catholic High School serves the young people of North County and beyond and helps direct them as they make their journey through life.