This is the third in a five-part Newsworthy series, Sweltering cities, looking at the impact of rising global temperatures on our daily living, learning and working conditions.

Year 12 student Ian Tjoelker is currently enrolled at Springwood High School in the Blue Mountains, a school which, until very recently, had no air-conditioning installed in its classrooms.

Springwood’s walls are constructed from brick and concrete and easily absorb heat, transforming learning environments into, according to Ian, a "solar oven". He says the heat was "unbearable, even with windows open".

“I remember the heatwave days at school, sitting in a pool of my own sweat, not able to focus on anything the teacher was saying, using my notebook to fan myself rather than take notes,” said Ian.

It was this excruciating heat that inspired Ian to found the 2Hot2Learn project, which aims to combat the effect of rising temperatures on primary and secondary schools such as Springwood across Australia.

In partnership with scientists from the Western Sydney University, 2Hot2Learn conducted a study on the effects of heat on student learning and classrooms with temperature sensors installed across 16 classrooms during the summer of 2018/19, an 87-day period.

Ian believes air conditioning should remain a secondary measure as it masks heat instead of preventing it.

The study found that temperatures in classrooms reached as high as 37.7°C with an average peak temperature of 31.5°C, well above the optimal indoor temperature for learning, which is between 22°C and 24°C.

Such temperatures can have severe longstanding effects on health, including exacerbation of pre-existing chronic illnesses such as diabetes, kidney disease and heart disease.

A 2019 research paper in Climate Change journal showed 2 per cent of deaths in Australia between 2006 and 2017 were heat-related, doubling to more than 4 per cent in the northern and central parts of the country.

Emma Bacon, founder of the Sweltering Cities project, says that rising temperatures have exposed a worsening crisis in educational inequality. She founded the not-for-profit organisation in 2020 to "work directly with communities in our hottest suburbs to campaign and advocate for more liveable, equitable and sustainable cities".

“It isn’t students from wealthy families who go to private schools with air conditioning who are strongly affected,” Bacon said. “It’s people who are learning in hot classrooms in poorer suburbs where the school parents have to fundraise to get air conditioning put in.”

High school teacher Elizabeth Maddox described her personal experience of the impact of heat on school learning, referring to her time in Mullumbimby on the NSW far north coast.

“In Mullumbimby, where we had no air conditioning, we kept spray bottles to squirt at students on hot days so they could think,” Maddox said. “As you can imagine, this isn’t an ideal way to teach.”

“There is little point teaching in extremely hot weather,” she said. “Teachers are dogged creatures and usually push through and do what we must; however, heat waves make work onsite very difficult.” Maddox sees an urgent need to address and mitigate climate change which she sees as the prime causality for recent heatwaves.

That's a sentiment echoed by Ian Tjoelker. “There are a number of proven methods of reducing the prevalence of classroom heat,” Ian said. There are macro and micro solutions: three of the most proven are changes to school architecture, installation of solar-powered air-conditioning units and immediate climate action.

“Schools must be built with heat in mind,” the Year 12 student said, suggesting passive cooling techniques such as shade sails, tree cover, adequate airflow and insulation could all help reduce the amount of heat from reaching classrooms.

Ian believes air conditioning should remain a secondary measure as it masks heat instead of preventing it, and can be both expensive and environmentally costly to run. Yet it can work in tandem with the aforementioned cooling techniques to create a more sustainable model of temperature regulation for classrooms.

“Real, effective climate action by all levels of government is the only way to stop the issue of classroom heat from getting worse,” Ian said. “In our changing climate, heatwaves are becoming more severe and occurring at a higher frequency, impacting learning outcomes for students across the country.”