A Sydney private school will transform itself into a fully co-educational campus after more than a century of predominantly single-sex education.

Barker College, on Sydney’s north shore, will become fully co-ed in 2022 from kindergarten to Year 12 in a bid to prepare its students for the realities of life outside the school gates.

It is at least the third historic NSW boys’ school to become co-ed in the past decade, after St Andrews Cathedral school in 2008 and The Armidale School earlier this year.

Principal Phillip Heath made the announcement to cheers from hundreds of students, teachers and parents at an assembly on Friday. The school has enrolled girls from years 10 to 12 since 1975.

He said that Sydney as a whole was out of step with the realities of the modern world through its emphasis on single-sex education.

“It’s a future-minded decision,” said Mr Heath, who was also responsible for St Andrews’ transition in 2008.

“The world has changed since 1890 when Barker was formed – the world is not going to be defined by gender any more.”

“It is something of a national shame that we are still considering these questions [about gender equality],” he said.

“I have a growing suspicion that the way Australian culture is expressing itself, and it’s not only boys’ schools promoting machismo, but the lack of awareness informed through another experience is diminishing some of our young people as they move through to university, and they are missing opportunities to learn respect,” he said.

He said research had shown there was no inherent advantage to single-sex education.

“It’s not rocket science, that matter is settled, you can’t put an argument one way or another on single sex.”

In September, the former president of American Psychological Association, Diane Halpern, said a review of 1.6 million students failed to find any advantages to single-sex education.

“We don’t have sex segregated workplaces so why would we have sex segregated schools?” she said.

“After graduation, virtually everyone will work for and with females and males – students need to learn mutual respect and the social skills of interacting.

“They need to learn how to interact co-operatively and competitively and these are important things that are learned in school – school is the only place where certain kinds of interactions occur.”

It is a sentiment echoed by the students at Barker College.

“Life is co-ed,” said 16-year-old Savannah Hughes. “It doesn’t make sense to have schools separated from that.”