St. Thomas High School, is both English / Punjabi medium, Co-educational School, run by Franciscan Capuchins of the Province of Krist Jyoti in North India, administered and managed as a Minority Educational Institution through St. Francis Services Society No. 625 of 1986 – 87, Registered under the Societies Registration Act XXI of 1860 as amended by Punjab Amendment Act 1957.
The School was opened on 2nd April, 1972. It is located in Mastkot Village near Kalanaur on the Batala Kalanaur Road. Studnets are Prepared for the P.S.E.B examination conducted by P.S.E.B. Chandigarh. Admission to school is open to children from all sections of the society.