On September 5, 1956, Mother Claire Alyosia rang the bell to open the school day for the first time at St. Thomas the Apostle School.  In their new four-classroom school, the Sisters of St. Joseph began educating the children of Chester Heights.  Mother Clair, together with Sister Margaret Gertrude, Sister Ann Esther, and Sister Claire Elizabeth were the first teachers at St. Thomas the Apostle School.  That first year there were 124 students, 53 boys and 71 girls.

In the years that followed, the school flourished and grew, doubling enrollment in just 10 years.  In 1967, four additional classrooms were added to give each grade their own classroom.  Lay teachers joined the Sisters and 310 students in their new classrooms.

In 1968, the Home and School Association was begun.  This formalized the growing parental involvement in the St. Thomas School programs, and recognized the partnership between parents, faculty, and administration that is fundamental to a successful Catholic education.

In 1985, the Sisters of St. Joseph withdrew from the parish, entrusting the school to lay faculty and administration.  The withdrawal of the Sisters, while disappointing, was vote of confidence that the parish would nourish and perpetuate Catholic education at St. Thomas the Apostle.  Certainly the Sisters' service at the parish was greatly missed, but the continuing strength of the school is the legacy of their 29 years of service to the parish community.

In 1996, St. Thomas the Apostle School was accredited by the Middle States Association of Colleges and Schools.  This accreditation, the result of a self-study process and detailed evaluation by a visiting team of education experts, confirms St. Thomas School's place in our children's future.  It is with confidence that the parents of St. Thomas and parishes throughout Delaware County send their children to St. Thomas School.  We have the confidence that our children will be prepared for the twenty-first century, educated in both the knowledge and values that are unique to Catholic instruction and to St. Thomas the Apostle School.

It is with confidence that over 208 families send over 340 children to St. Thomas the Apostle.