Under the direction of Father Francis J. Hertzog, the first St. Joseph School building was constructed in 1914, on Leishman Avenue. The school opened for first through sixth grade in 1916. However, records show that some children attended the school in 1915, while it was still under construction.
The Sisters of St. Joseph from Baden came to staff the new school. They lived on the top floor of the building for about two years until they were able to move to a convent, or rather until the convent was able to move to them. The convent was the old rectory building that had been converted and moved on rollers to a lot near the school. An old tool house was moved beside the rectory-turned-convent, and it was converted into a small chapel. A door was added so that those attending daily Mass at the chapel could enter without disturbing the convent.
In 1919, Father Hertzog started a high school program at St. Joseph School. The program began with a two year commercial course, with the hopes of expanding to a four year curriculum in the future. The high school program opened to 10 students — 7 girls and 3 boys—who had all graduated from the eighth grade at St. Joseph School.
One of the Sisters was chosen to teach the high school program. However, due to a teacher shortage, the same Sister also had to teach fourth grade. In order to have enough time to instruct both age groups, the Sister taught fourth grade during the day, while the high school class attended a full day of school that included working on assignments. Then, in the evenings the Sister would instruct the high school students, check their assignments, and teach new material.
Unfortunately, the high school program did not last. It was closed after the first year. The ten students were left in a bind, especially after the superintendent of public schools refused to admit the St. Joseph students, citing a lack of proper supervision. These students had to go out and find work rather than continuing their education.
In 1939, a new convent was constructed and was made an addition of the school building. The new structure connected both floors of the convent to the school, and consisted of two classrooms, a meeting room, 14 sisters' rooms, a community room, a chapel, a dining room, a kitchen, parlors, an office, two practice rooms, and a laundry room.
When the old Lyceum was razed in 1963, more construction projects were able to move forward. Plans were made for a new school and gym. The project was completed in 1964, and the school was dedicated on Aug. 26, 1965, in time for classes to begin in September. Bishop William G. Connare presided over the dedication ceremony, which started with a procession into the church, followed by a homily and benediction from the bishop. Then another procession took place from the church to the new school, where the structure was blessed. An open house for parishioners and friends followed.
The new school was made of red brick, and provided four new classrooms, administrative and nursing offices, a library, a music room, and a gym and shower rooms. The cafeteria and kitchen in the old school were also renovated. The seventh and eighth Grade students were going to be moved to the new building, while younger students would remain in the old one. A kindergarten program was added in 1981.
In 1998, St. Joseph School assembled a technology committee. The groups' main focus was to research and enact changes in the school's technology systems and programs. The committee came up with the NetDay plan, a three phase project that updated all facets of technology in the school. The first phase of the project had parishioners, parents, students and other volunteers wiring the new building. The second phase called for the wiring of the old building, which required more planning, and presented more problems thanks to the old building's construction. The final phase of the project included providing internet access for all students, teachers, and administration. The Internet and educational resources could be accessed from all classrooms, meeting rooms, and offices. The number of computers in the building was upgraded from 23 to 128.
The project was completed in December, when the school unveiled its new website and computer network at a meeting for parents and alumni. The website was developed by students with the help of young-adult mentors from the parish. The site was to be maintained by students, and included a school schedule, a sports page, cafeteria menus, a parent handbook, Parent-Teacher group pages, and other information about the school.
The NetDay project received support from many community businesses. MicroPower Systems Inc., a New Kensington-based computer systems integration company became the school's service provider, and also donated software instruction for the teachers. Other businesses, such as BuildPen, Bell Atlantic, Storm Technologies, and ALCOA, donated equipment.
In April 2000, members of St. Joseph, St. Margaret Mary, and Mount St. Peter schools met to listen to a proposal that outlined a plan to establish a middle school program, sixth to eighth grade, for students of all three schools. The program would be housed in one of the two buildings at St. Joseph School, and would be established to enhance the educational needs, and provide more youth ministry, athletic, and other extracurricular opportunities for students. The subject of a middle school was broached in 1991, but was not pushed forward. The 2000 proposal never came to fruition either.
In fall 2002, Mary Queen of Apostles School, a regional school, opened to serve students in preschool through eighth grade. The school was formed from the merger of St. Joseph, St. Margaret Mary, and Mount St. Peter schools, and catered to students in the New Kensington, Lower Burrell, and Arnold areas. The school used two of the former school locations for classes: the former Mount St. Peter School on Freeport Road housed preschool through third graders, and the former St. Joseph School on Leishman Avenue housed the fourth through eighth graders, as well as the main office. Site selection was based on projected enrollment, the space availability, and proximity of the sites. Cathy Collett, the former principal of Mount St. Peter School, was named the first principal of Mary Queen of Apostles Catholic School.
Today, Mary, Queen of Apostles Catholic School still instructs students at the Freeport Road site, but opened a new site for fourth through eighth grade students during the 2016-17 school year. With the permission of Bishop Edward C. Malesic and the MQA Board of Pastors, Greenwald Memorial School, a former elementary school of the New Kensington Arnold School District was purchased for $525,000. The former building closed due to a school consolidation in the summer of 2014. Once purchased, MQA volunteers spent the summer of 2016 sprucing up their new home to create an inviting space for students.