"It doesn't matter which political party, they all make good posters," laughs 12-year-old student organiser Alison.

"But they all have some learning to do. Five-year-old's understand [climate change] better than politicians do."

Since June, students like Alison have been busy wrangling permits, organising food trucks and haggling over public liability insurance for what is tipped to be Canberra's biggest climate strike yet.

This time around they'll be joined by those walking out of their workplaces and universities as the strikes hit the mainstream.

Student organiser Aoibhinn Crimmins, 17, said that meant kids had much more help than they did while organising the last protest in March, which drew about 5000 to Garema Place, 150,000 across Australia and 1.5 million worldwide.

"Back then it was pretty much us on our own, it was a miracle it all came together," she said.

"But this time it's also a much bigger event, we're expecting 10,000 so there's still just as much work for students. And we're juggling school, exams."

Anya Khan, 12, has been helping line up police permissions for the big day.

"It's a lot of emailing back and forth," she said. "A lot of other stuff like the posters we've sourced or had donated."

The school strike movement, inspired by 16-year-old Swedish activist Greta Thunberg, has attracted the backing and guidance of organisations such as the youth-run Australian Youth Climate Coalition.

But students hit back at suggestions the strikes were being secretly masterminded by left-wing lobby groups frightening kids out of classrooms.

When The Canberra Times visited students at their final meeting for the Canberra leg of the protest on Wednesday, organisers were keeping cool heads.

While there was definite concern about the rapidly warming climate ("I'm very, very scared" said 12-year-old Arianne as she prepared for her upcoming musical performance at the strike), most kids were holding fast to the science, checking and sometimes correcting facts.

"The adults helping out have been really respectful in not taking over," Aoibhinn said. "We're calling the shots, we're telling them to do, what we want."

What they want is more ambition - a target of 100 per cent renewable energy generation and exports for Australia by 2030 and funding for a "fair transition" into new jobs for fossil fuel workers and communities.

They are also demanding an end to all new fossil fuel projects - including the Adani development threatening the Great Barrier Reef up north. Experts warn opening up that huge untapped coal reserve could torpedo efforts to curb emissions and so stop runaway global warming.

Amelia Hollo, who addressed ACT politicians on Wednesday at the invitation of the government, said that while the territory was leading the charge on climate action, it still wasn't keeping pace with the science.

This week, the ACT announced plans to achieve net zero emissions by 2045, as it rapidly closes in on its target of sourcing 100 per cent of its electricity from renewable energy by next year.

"It's kind of disappointing that even the best is just doing the bare minimum compared to what scientists say," Amelia said.

Almost every year of their young lives have now ranked among the 20 hottest on record but Aoibhinn agreed she learnt little about the real speed of global warming at school.

"Some teachers are great, you'll get maths teachers taking you through the latest IPCC report," she said. "But others are too scared to teach it properly because they think it's too political.

"We need to know how urgent it is. We want teachers to be braver."

Last summer again brought record-breaking heat and natural disasters - along with a crushing realisation for eight-year-old Sebastian Grey that time was running out.

"We need politicians to listen to us now, this year," he said. "They just think about money, well we won't have any money if there's no planet."

Academics, churches and unions, including the Australian Education Union, have all backed the strike and many businesses are letting workers take time off for the day.

The ACT education directorate said students striking with their parents' permission wouldn't be penalised, after the government again supported the strike as important real-world learning.

Teachers could arrange a class excursion to the strike, attend on their lunch break or apply for leave for the day, a spokeswoman said.

There were a range of professional learning opportunities for teachers focused on how best to teach sustainability and climate change, she said.

The Canberra Times