A one-teacher school began in the hall under the Castle Hill Seventh-day Adventist Church.
A two-classroom school was built on two acres behind the church. Until 1968, the Castle Hill church took full responsibility for the school. That year, four surrounding churches, then called the Hills District, combined to operate the Adventist School.
With financial assistance from the Greater Sydney Conference’s 'Support our Schools' scheme, the school completed extensions including one extra classroom, offices, toilets and an assembly room. Upgrading of the playground was also carried out at this time.
The school continued to grow, and in 1978, the next stage of the building was completed.
Major building works commenced, where a large building project began. This provided the school with a new library, computer room, reception area, offices and staff room first used in 1997.
The new Early Learning Centre was opened, and a commitment made to developing a Middle and Senior School.
By 2010, it became obvious that the Castle Hill site was unable to sustain greater growth, and the Middle and Senior Schools (Years 5–12) were relocated to the Kellyville campus.
On 25 October 2012, NSW Senator Doug Cameron officially opened the Multi-Purpose Centre, the first permanent building on the Kellyville campus.
The College now has two outstanding campuses in the Sydney Hills District: a dual-campus school with an Early Learning Centre and Primary School (Kindergarten – Year 4) located at Castle Hill, and a Kindergarten to Year 12) campus at North Kellyville.
The College continues to serve the Hills District community and provides a nurturing environment focused on learning, personal development and opportunities for service.