St. Thomas Aquinas Catholic School is home to 888 students and is the largest Catholic PK-8th grade school in the state of Texas. Opening its doors in September 1947, St. Thomas Aquinas Catholic School had humble beginnings serving as an extension to the families of the Sacred Heart Cathedral. Known initially as Sacred Heart School #2, 250 students began their St. Thomas Aquinas experience in four classrooms with The Sisters of Divine Providence as the first teaching order at the school.

With Monsignor John T. Gulczynski thoughtfully serving as the founding pastor, St. Thomas Aquinas Church was erected in 1955, following several years of the community celebrating Mass in the school auditorium. Today, St. Thomas Aquinas Catholic Church serves over 6,000 households.

Parish and school growth, as well as the growth of the East Dallas community, led to the expansion of the school to two campuses. In 2005, a successful capital campaign made it possible to acquire and renovate the First Community Church building and property located on Mockingbird Lane, approximately .25 miles from the church and school. Known as the Lower School, the Monsignor John T. Gulczynski Early Childhood Center, serves 350 students in PK4 through 2nd grade.

An additional 2.68 acres of land, adjacent to the main campus, was purchased by the parish in 2011. The acquisition again expanded the footprint of St. Thomas Aquinas Catholic Church and School in our community and serves our students as multi-use outdoor space and athletic fields.

In September 1996 and September 2012, the U.S. Department of Education recognized St. Thomas Aquinas Catholic School as a National Blue Ribbon School of Excellence. A recognition limited to only 50 private schools in the nation each year. In 2013, at the Bishop's request, St. Thomas Aquinas moved to a President/Principal administrative model due to its growth. St. Thomas Aquinas Catholic School is accredited by the Texas Catholic Conference Education Department and the Southern Association of Colleges and Schools.

In 2022, St. Thomas Aquinas Catholic School celebrated 75 years of educating students in our community and will proudly continue to serve the families of St. Thomas Aquinas Catholic Church for generations to come.