The school commenced in 1995 with enrolments on two campuses — Auburn (Years 9 to 12) and Regents Park (Years 7 and 8). Trinity has a unique structure with each campus administered by a campus director, who is responsible for the day-to-day operations. The principal, assistant principal, director of studies and religious education co-ordinator have cross-campus responsibilities.
Facilities: An extensive refurbishment program has been undertaken on both campuses, with new technology, library and science facilities.
Curriculum: All eight Key Learning Areas are taught from Years 7 to 12. Links have been established with the six primary feeder schools to ensure continuity of curriculum from Kindergarten to Year 8. Students in Years 9 and 10 have a great range of elective subjects to choose from. Students in Years 11 and 12 have a wide variety of subjects to choose for the HSC, including most traditional subjects, vocational curriculum frameworks and TAFE courses. A large number of Australian competitions occur in many subjects. All students follow an integrated religious education program from Years 7 to 12, and the Catholic ethos of the college is vigorously promoted in all of its activities.
Sport: The college has a proud tradition and participates in the MCS and MCCS competitions in 20 different representative sports, and another 19 are offered as internal sport.
Extracurricular activities: Debating, public speaking, Mock Trial, music, choir, and drama are enthusiastically supported. A creative and performing arts evening occurs every year.
Welfare and personal development: ESL classes are provided for students from non-English-speaking backgrounds. A strong and caring pastoral program operates and a number of qualified school counsellors work with the students and staff. Special support is given to ESL and special needs students. Extension classes operate throughout Years 7 to 10 as well as other targeted gifted and talented activities.