Students celebrated the milestone with a flash mob in an assembly to congratulate Mr Higgs.

They also showed a video of the school captain of the school from Mr Higgs' first year as headmaster, who recalled the first message Mr Higgs delivered in an assembly: open hearts, open mind and open books.

Mr Higgs said he wanted students to graduate from the school with an understanding of the world and of other people.

Inspired by another school, he placed a plaque in the performing arts centre to inspire students: From those to who much is given will much be required.

He started at the beginning of 1995, spending time at the school in the fourth term of 1994, getting to know staff and students.

He came to Ballarat after 22 years with Melbourne Grammar, on and off, chasing a lifestyle change in the country. He was Melbourne Grammar's head of science and ran the boarding house.

When he started at Ballarat Grammar School, the school had less than 800 students and it now has 1450.

He started the school's City Campus, where year 9 students spend three weeks in Melbourne learning about the city and how to get around it.

The school has a campus in Flinders Street with four full-time teachers, which other schools now use for a similar program.

Mr Higgs also started the school's grade 4 farm campus, which opened this year. "We started agriculture here about 15 years ago, and then we acquired the farm about six years ago to expand the agriculture, and we thought how can we make best use of the campus."

The Wendouree Centre for Performing Arts was also one of Mr Higgs' projects, with a vision for it to be a great school and community space.

The next project for the school is a synthetic surface on one of the northern ovals of the school, suitable for hockey, netball and

athletics.

The student group is more diverse than when he started, with refugee students and indigenous students from remote areas of Australia all coming to the school through an outreach program.

Ballarat Grammar is part of the Victorian Ecumenical System of Schools for funding purposes and international group Round Square, which the school joined in his second year.

Last month, he travelled to Jordan with students for the international Round Square conference at another member school.

"For a week before the conference we worked in a Friends of the Earth nature reserve, about only 30 kilometres from the Syrian boarder, rubbing shoulders with every day Jordanians," Mr Higgs said.

"It's terrific for students to see how they get along, so close to Syria and Iraq, and there in Jordan, Christians and Muslims get along."

nicole.cairns@fairfaxmedia.com.au