St Mary's College, in conjunction with St Edmund's College offers a wide variety of ensembles for instrumental and vocal students of all abilities. Ensembles rehearse once per week and perform at a variety of events throughout the year including Performing Arts Nights, Cultural Showcase, Queensland Catholic Schools' and Colleges' Music Festival, Liturgies and Masses, Little Kings Movement, Awards Nights and other school and community events.
The College also has a strong instrumental music tuition program, offering students the opportunity to learn an instrument. Students in Years 7 to 9 may receive up to one year of free instrumental music tuition, funded by the P&F. The program caters for all levels of ability, from beginner to advanced.