This summer, as thousands of school students across Australia sweat it out in hot classrooms, an elite team of "eco-rangers" will be policing the halls (and teachers) of one Canberra primary school.

Their job is to help Garran Primary do its part for the planet (and hang on to its title as the ACT's sustainable school of the year), checking lights haven't been left on, computers are put to sleep and recycling bins are filled up properly.

In a rapidly warming climate, sustainability has become a familiar term around the schoolyard. All public schools in Canberra now have solar panels, some even generate income. By next year, the territory's newest school in Taylor, the Margaret Hendry School, is expected to become its first carbon neutral campus, as the ACT moves to 100 per cent renewable energy by 2020.

But experts say schools need to get smarter about heat management too, warning soaring temperatures are already taking a toll on student learning.

Recent research from Western Sydney University found cool environments are even more important for kids' concentration than adults, off the back of a 2018 Harvard University study that revealed heat exposure led to poorer learning outcomes.

Because of their higher metabolic rate, children prefer room temperatures to be two to three degrees cooler than adults, researcher Sebastian Pfaustch says.

While kids are vulnerable to heat stress, no state or territory in Australia has a set magic number or temperature threshold beyond which students are sent home in summer. Dr Pfautsch said enforcing a mandatory classroom temperature of say 22 degrees would be difficult but stressed a serious look at how schools could adapt to higher temperatures was long overdue.

“There’s guidelines but no actual standards that are compulsory,” Dr Pfautsch said.

“We’re going to get more days above 35 degrees, we will get up to 50 degrees soon so this is critical.

“What chances do we provide [students] in Western Sydney or Canberra if we put them through these hot temperatures?"

Health expert Liz Hanna from the ANU's Climate Institute agrees the problem is not being taken seriously enough by governments.

To survive Canberra's notoriously frigid winters, heating had eventually been installed in its schools, she said, but the same priority had not been given to cooling, despite the capital’s perhaps equally punishing summers.

“Extreme heat can kill you because you can’t keep your body in its normal temperature range," Dr Hanna said.

When the mercury climbs, exercise outdoors such as for a PE class became of particular concern, she said. Cooling was not a "luxury", she stressed, and schools and departments had a duty of care to provide the right thermal environment for learning - and teaching.

“Teaching is a high energy activity in itself, you’ve got to have your wits about you.

“The curriculum is so busy nowadays, we can’t afford to lose learning time...but we know from reports from teachers that kids get lethargic on hot days, it’s a physiological response, a self-preservation thing, it’s not something we should override, but it’s difficult when 'we’ve got to do our learning'.”

Over the border, both NSW and Victoria are rolling out large-scale air-conditioning programs in classrooms.

The ACT education directorate said it was implementing its own heat mitigation program in public schools to ensure they were "conducive to learning", including tree planting as well as insulation and glazing upgrades. While it did not provide the number of schools with a majority of air-conditioned classrooms, a spokeswoman said all students had access to cooling in at least one priority area of the school.

"High temperatures are experienced every summer in Canberra, and work is under way to adapt ACT public schools to make them more comfortable for students and teachers," she said.

“Due to the high cost of installing and operating air-conditioning units, artificial cooling is not available in every classroom.”

In the 2017-18 financial year, $1.96 million was spent on the program across 42 schools, with air-conditioning units listed among the new cooling solutions installed.

A new school design brief for upcoming builds also draws on smart design, natural cooling and energy usage to keep schools comfortable.

In December, almost $37,000 was also spent on bushfire mitigation at Black Mountain school, government invoices reveal.  A spokeswoman said all ACT public schools in areas prone to bushfire were assessed ahead of the season, including Black Mountain, Birrigai, Bonython, Fraser, Hall, Jervis Bay and Tharwa.

At the ACT teacher's union, Glenn Fowler said he was hearing good things about upgrades in ACT schools so far but said every classroom needed heating and cooling solutions in place within the next few years.

While cycling kids through the library or gym on hot afternoons was not solving the problem, Dr Pfaustch said locking kids indoors in air-conditioning was not necessarily a silver bullet either. Building codes as well as outdoor spaces needed to be redesigned to allow for smarter air flow and urban canopies, he said.