The school was started as a part of the mission programme of Malankara Mar Thoma Evangelistic Association under the leadership of educational protagonist Rev. C.I. Abraham, Venmony. As the wise men of Keezhillam foresaw the institution would become a blazing trail in the development of the village, the venture created wide positive waves among the people. They all contributed with land, financial and moral support. The dream came true in 1922 and the middle school was started. Mr.C.T. Mathew Ayroor (Later Rt. Rev.Dr. Mathews Mar Athanasius) was called in as the first Headmaster. The boarding home was also started with Mrs. C.I.Abraham as the first warden.
The school has a compound of over 14 acres and Three academic classifications, higher secondary, high school and upper primary. We have mainly three blocks, the higher secondary block, high school new building and upper primary, staffroom and office block. A sevens football ground, a huge athletic and foodball stadium, volleyball court, kho-kho court, shuttle badminton indoor and outdoor and table tennis facilities are available for physical development of children. Library, science laboratory, IT laboratory, audio visual lab, library and other infrastructural facilities are available in the school.
St Thomas HSS is a great campus because it respects all children and provides a supportive and positive environment for learning and development.
Admision opened for the year 2015
Run Kerala Run January 2015
Arts day celebration 2015
Annuel day celebrations starting on 30th January 2015
Alumni portal inauguration on 30th January 2015
Sports day celebration 2015