On April 1, 1949, Father Marcus Valenta and Mr. R. H. Hancock met with the Archdiocesan Building Board in San Antonio to discuss the building of a six-room school building that would cost approximately $90,000. On April 26, 1949, Mr. R.H. Hancock approved the placing of the proposed school building on the site of the rectory, which he offered to transfer at his own expense, with certain exceptions, to another place on the property. Father Valenta approached Mother M. Angelique, Superior General of the Sisters of Divine Providence, San Antonio, Texas about providing two Sisters for the school opening in September 1949.
On August 17, 1949, Father Valenta, Mr. R.H. Hancock, and his daughter, Mrs. Dan Gillean, requested two sisters for the school. Sister M. Silverius and Sister M. Evangelista and Mrs. Jerome Slivia opened the school for the 1949-50 school year. Classes were conducted in the parish hall (the second church) due to a materials shortage, which hindered the construction of the new school building.
The first year's enrollment had reached 117 by January 6, 1950 for the first three grades. By August 17, 1950, the faculty increased to five teachers with three lay teachers on staff. The first principal of the school was Sister M. Silverius, C.D.P.
The contract for the construction of the school was signed on July 23, 1949 with Vaclavick Construction Co. of El Campo. The contract price was $100,444.86. Archbishop Robert E. Lucey laid the cornerstone on December 11, 1949. The school was sufficiently completed by September 24, 1950 to enable classes to be conducted.
On January 30, 1953, Father Valenta approached the Archdiocesan Building Board for permission to build additional three classrooms and a gymnasium. The estimated cost would be approximately $175,000 to $180,000; however, another proposal was presented at a later date. On August 27, 1953, the parish purchased the old band building from the Northside Public School across the street from St. Philip School. The structure, 24 feet by 60 feet, was acquired for $1,000 and was fondly known as the "university" or the "pink house." On January 21, 1955, Father Valenta and the parish building committee proposed to the Archdiocesan Building Board plans to build a new rectory, eight classrooms, and an auditorium-gymnasium for an estimated cost of $280,000. On June 28, 1955 Bhomann Brothers, contractors from Schulenburg, Texas, were awarded the bid for the construction at $276,420.
In 1963, the school added additional two classrooms, a teacher's lounge and library.
In 1976, the parish hall was dedicated and housed the school cafeteria and three classrooms that are being utilized by the school today.
In 1988, the parish purchased Herder Field, which is used today as the football field for the school and athletic purposes.
In 1995, the school opened a full day kindergarten program.
In 2004, the school added a preschool program for three and four year old children.
In 2012, the school opened a new gymnasium, fitness center, music center, fellowship hall, stage and the R.H. & Irene Hancock Early Childhood Center. The Early Childhood center features six classrooms for the school's Pre-K and Kindergarten students. The Nancy Krenek memorial recess pavilion was added.
In 2018, the school refurbished the four original student restrooms in the main school building to bring the facilities up to ADA standards. During this time, the school’s infrastructure and lighting was updated and the ceilings were lowered to improve efficiency.