The enrolment of the Junior School is approximately 360 boys. Classes in Years 5 and 6 ordinarily consist of boys of differing levels of ability, however there is one Learning Support class in both Years 5 and 6 as well as a Year 6 Extension Class. Boys are also withdrawn in both years to take part in an extension programme that runs throughout the school year.

The curriculum includes Religious Education, English, Mathematics, Science and Technology and HSIE (Human Society and its Environment). Specialist teachers and facilities are available for Visual Arts, Music, Personal Development/Health/Physical Education, Languages and Library. Languages taught include Italian, French and Chinese.
In addition, the class teachers join specialist teachers for Games lessons (during which boys are skilled in games such as Cricket, Rugby, Soccer and Basketball), and Strings lessons (during which boys are taught either the violin or the cello).
Junior School boys have access to Information and Communication Technologies through classroom computers, a computer bank in the Junior School Library and through the College Computer Laboratories.

The Junior School normally takes part in competitions, organised by the UNSW, in Mathematics, English, Computer Studies and Science. As well, boys are chosen to compete in the Da Vinci Decathlon and Mathematics Olympiad. Learning Support is provided through a full time Learning Support teacher who works within classes and takes small groups.

The Junior School organises annual community building events including Grandparents Day, Dad’s Breakfast, Junior School Parents' and Friends' Dinner, Welcome Mass, Fundraising Day and every year has a Sports Dinner.