An explosion in the number of high-rise apartments across our capital cities is dramatically driving up student enrolments, resulting in “jam-packed” public schools.

The overcrowding is due to the growing number of families with school-aged children choosing to live in smaller dwellings close to the CBD, rather than houses in the suburbs.

State governments did not anticipate the trend and are now playing catch-up by installing demountable classrooms on school ovals and quadrangles to accommodate the extra students until new permanent facilities are built.

Brisbane State High School — already the largest public high school in the country — is under enormous pressure, as thousands of apartments spring up in suburbs within its inner city catchment.

In just four years, the number of students there has jumped from 2,269 to 3,145, meaning the school is now well over capacity, despite the recent addition of 40 extra classrooms.

A draft report on enrolment pressures at the school shows the problem is only going to get worse.

The report, which was produced by the consultancy firm KPMG and has not been made public, said the school will have to accommodate another 1,000 students in the next decade.

Students who spoke to ABC RN’s Background Briefing program did not believe the school could cope with such an increase, arguing the environment there already resembles morning peak hour.

“I thought traffic was only for cars until I came to this school,” one student said.

“It’s sort of like rush-hour time. It’s really jam-packed, people shoving and pushing,” said another.

Families trading space for convenience

The rapid growth in enrolments at the school is also driven by its strong academic record, which attracts more families into the suburbs of South Brisbane and West End, increasing demand for apartments and exacerbating the overcrowding.

So far the trend is most obvious in the junior years, with KPMG’s draft report stating that 40 per cent of classrooms through grades 7 to 10 exceed size targets.

“My Year 8 class for humanities was 35 people,” another student told Background Briefing.

“I guess a class of 35 would be really difficult on the teacher, not just the students.”

Since the 2011 census, the number of children aged 15 and under living in Brisbane’s inner city has risen by 40 per cent, suggesting a growing number of families are trading space for convenience.

This shift is even more pronounced at the local primary school in West End, where a staggering 70 per cent of students live in apartments.

Sara Vogelsberger and her husband, Zac, have been raising their family in a small flat a short walk up the road from the school.

Although they can afford to buy a house in a more spacious suburb further south, they instead decided to convert a laundry into a third bedroom so they could remain closer to the action.

“We live in West End because of the benefits of living in a place that has a great community and the sort of lifestyle where you feel like you live in a village,” she said.

“There’s access to everything you normally need, shops, doctors, and schools but then there’s also, within walking distance, major cultural institutions.”

But demographers in the education department, whose job it is to calculate enrolment projections, have been slow to adjust their modelling in response.

“I think, in the past, education demographers have missed the mark when it comes to the types of families or types of people moving into inner city units,” said Queensland’s deputy premier and infrastructure minister, Jackie Trad.

“Clearly there are a number of people who choose to live in a city with school-aged children to be close to work in the CBD and to be close to great social infrastructure.”

‘A very big planning failure’

As recently as late last year, Queensland’s education minister, Kate Jones, was still receiving advice downplaying the link between increased development in Brisbane’s inner city and school overcrowding.

“I am advised the majority of this development is high density apartment buildings, which generally have a very low percentage of children,” the minister wrote in a letter to a concerned parent on October 2, 2016.

The concerned parent was Carla Mullins, who lives in an apartment and whose son attends the primary school in West End, which is also over capacity.

She said the minister’s remarks suggest she is out of touch.

“That may be an old fashioned view of the Australian way of life but it’s changing,” she told Background Briefing.

Ms Mullins said the failure to predict and respond to overcrowding at local schools represented a “very big planning failure”.

She has been lobbying for a new school to be built in South Brisbane or West End but so far the state government has delivered only short-term solutions.

It recently funded eight new permanent classrooms, designed to increase West End primary school’s capacity to 977 students by 2021.

Beyond that, there is no plan.

Given the rate at which the student population is growing, Ms Mullins argues the additional capacity the extra classrooms create will likely be filled much sooner than 2021.

“It’s too little, too late,” she said.

Kate Jones declined to be interviewed. Her office referred Background Briefing to the deputy director general of the education department, Jeff Hunt, who also said he was unavailable. The department would not allow any school principals to speak to the program.

‘Flawed forecasts’ saw Sydney schools closed

These same overcrowding issues are afflicting Sydney, where a decision to close a number of schools more than a decade ago is now coming back to bite the NSW Government.

In response to declining enrolments at inner city public schools, a parliamentary inquiry was held in 2002 to determine which of them should survive.

It heard evidence the schools did not have enough students to offer a wide curriculum, their facilities were neglected, and families were increasingly showing a preference for private schools.

It was argued that enrolments at these schools were unlikely to ever bounce back.

Professor Peter Phibbs, a geographer and sociologist at Sydney University, appeared before the inquiry to challenge this assumption, warning it was based on flawed forecasts.

“I was a housing researcher and the forecasts were done by demographers who I think were maybe just a bit wedded to their models and past trends,” he told Background Briefing.

“I was certainly talking to a lot of younger people that were expressing a strong preference for staying in an apartment in the inner city with their kids rather than relocating to the suburbs both for lifestyle reasons, but also for price.”

But Professor Phibbs said his views were dismissed.

“I was more or less told … by some government politicians at the time that I was living in an ivory tower and everyone that had kids would want to move to the suburbs and live in a separate house, because that was such an obvious thing to do.”

The inquiry recommended that some schools remain open but others, like Redfern Primary School, were closed.

Now enrolments at the surrounding Bourke St and Erskineville primary schools are booming and there are concerns about overcrowding.

“It was clearly a huge mistake,” said public education advocate and author, Jane Caro.

“Exactly what the activists who were fighting to keep those schools open said would happen has indeed happened.

“It would be good if people listened a little harder to ordinary citizens. Sometimes they actually know what’s going on in their community.”

Caro said with inner-city public schools now bursting at the seams, it was clear the demographers advising the then Labor government were incorrect.

‘Wrong information leads to wrong decisions’

NSW’s Liberal Government has since taken steps to address the shortcomings in the demographic modelling used by the education department, but only after persistent lobbying from an especially determined parent.

Steph Croft, a trained analyst who has previously worked for the Australian Securities and Investments Commission, began to question the department’s student enrolment projections in 2011.

She found that, in trying to predict future student numbers, the education department was not accounting for unborn children, immigration rates, and the number of families living in apartments, even though all that data was readily available.

“The figures they were using were resulting in them showing that school numbers would drop off and the problem would go away,” she said.

“In actual fact, we realised that when they adjusted for those flaws in the data, that in fact there was a big enrolment surge coming.”

Ms Croft took her findings to a number of Liberal MPs, including Gladys Berejiklian, now NSW Premier.

The MPs responded by establishing a centralised demography unit within the planning department, while also removing a number of schools from an asset sales list.

It was a victory for Ms Croft, but she wishes the problem had been fixed sooner, before previous governments closed down so many schools.

“It shouldn’t take volunteer parents to be uncovering the sort of flaws that we found, because wrong information leads to wrong decisions,” she said.

The NSW education department insists its demographic modelling is robust, adding it has been reviewed by three external agencies in the past 18 months.

It predicts 164,000 extra students will enter the public school system by 2031.

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This post originally appeared on ABC News.