In order to slow the spread of COVID-19, many states and territories have urged parents to keep their children home from school where possible.
University of Melbourne public health researcher Lisa Gibbs said it was important to provide children with age-appropriate ways to make them feel active and capable during the pandemic.
"It's easy in times of danger, which essentially this is, to be so concerned with protecting the child which obviously is of utmost importance," Professor Gibbs said.
"But in protecting the child we can sometimes treat them as passive and vulnerable, which doesn't make them feel safe.
"So these sorts of activities are really helpful in providing a sense of agency in children, that they can cope with what's happening and they're making a contribution to others as well."
Professor Gibbs said in times of disaster, two patterns were very common — community mobilisation, where people banded together, and community deterioration, where social supports fell apart.
"So what these initiatives from children are doing is really contributing to social mobilisation," she said.
Why adults are joining in, too
But it's not just children picking up the chalk during the COVID-19 pandemic.
Artist Suse Scholem has been curating different quotes for the streets around her Melbourne suburb.
"It's cathartic, joyful and empowering for me, and beautiful to feel a sense of the connection and hope that it might bring others," she said.
Centrelink staff in Melbourne and teachers at Tasmania's Lauderdale Primary School have also arrived to work to chalky messages of thanks.
Sharon Bailey, from Kalbeeba near South Australia's Barossa Valley, has been trying to solve the mystery of who has been leaving chalk trivia questions along the route of her morning walk.
They first popped up a fortnight ago, with questions ranging from how many horses there were in an adjacent paddock, what to do with your dog poo (the answer: an arrow pointing to the bin), and who won the 2000 grand final.
"It's just really good, and all positive, and cheers everybody's walk up," Ms Bailey said.
She said the only clue as to who wrote the messages are two initials — E and D.
"I'd like to thank whoever they are … it's a real positive thing," she said.
How chalk is binding together communities across Australia
Research shows if people feel part of their communities, that can be protective of their mental health outcomes during times of disaster.
"So they're not small measures, they're actually really important," Professor Gibbs said.
"Anything like that can make a contribution, not only for the person who is doing it, but also for the person who encounters it."
Healthy cooking teacher Kristen Pavez said it had been empowering for her two boys to add rainbow pictures and a message to "be kind" to their Perth street.
Schools are closed to most children in Western Australia, so with much more time at home on the horizon, Ms Pavez said "there'll be a lot more driveway art".
Just south of Cairns, relief teacher Maria Holt and her three-year-old Leonardo used homemade chalk to brighten up their street.
Ms Holt has been out of work as a casual relief teacher and her son stopped going to daycare more than a week ago.
"It's a weird season in our collective experience and a tough time for many," Ms Holt said.
She said while she hadn't had any comments from her neighbours yet, "I did see the postie slow down to have a good look".