Secondary Years 7 - 12

Secondary students have access to a range of purpose-built facilities on the Truganina campus, including the Horsburgh Centre (dedicated to Years 7 and 8), the Geoffrey Ryan Centre (Year 9), a sports and aquatic centre with a swimming pool, a purpose-built STEM laboratory for senior science students, and modern learning spaces designed to support twenty-first century education.

Westbourne Grammar School employs a Community of Practice model underpinned by the strong moral purpose that every child can succeed. The school's vision is 'Shaping Learners Who Inspire the World', supported by core values of Community, Creativity, Scholarship and Courage. The school also draws on Joseph Campbell's concept of 'the hero's journey', incorporating themes of the call to adventure, mentors, ordeals and triumph over adversity into life at Westbourne.

Yes. In 2019, the school was selected as the winner in the independent schools, Melbourne western region category of the inaugural Schools that Excel award run by the Age newspaper, which was described as a reflection of more than a decade of improvements to the VCE median study score.

Secondary students can participate in a range of signature events and productions, including a professionally produced senior musical staged at the Wyndham Cultural Centre in Werribee, an annual music concert at the Melbourne Recital Centre, and Westbourne Celebrates at the Melbourne Convention Centre — events that showcase the talents and achievements of students in Years 3–12.

The secondary campus is located at Truganina in Melbourne's western region. The campus features an expansive Sayers Road frontage that includes the Geoffrey Ryan Centre (Year 9), the Horsburgh Centre (Years 7 and 8), native bushland, landscaped grounds, and sports facilities.