Students at Sydney high schools should be made to wear hats as part of their uniform, parents, principals and health experts say, warning the current regulations, which only "encourage" sun protection, do not go far enough.
The NSW Department of Education's school uniform policy requires schools to establish school uniform requirements in consultation with their communities, but does not enforce the no-hat, no-play policy of the state's primary schools.
It has prompted concerns that the sun-safe practices of childhood may be undone throughout teenage years.
Schools such as Terrigal High "encourage students to be aware of the harmful effects of the sun on exposed skin" but they contrast sharply with Queensland, where public schools such as Maryborough make it "mandatory for sun-safe hats to be worn outside of the classroom".
Catholic and many independent high schools also follow the department's policy on sun safety for students while they are outside.
A parent, who asked not to be named to protect her child's identity, said the situation at her daughter's private school had become "ridiculous".
"Girls can't wear hats because they aren't a part of their uniform," she said. "There's no sun-safe policy."
Another parent at a north shore public school said teenagers were less likely to wear hats because they "weren't seen as cool".
"It risks undoing all the good practices they learnt during primary school," she said.
P&C Federation President Susie Boyd said the federation supported the encouragement of wearing hats in the sun especially with the increase in the number of melanomas being reported.
The concerns come as the NSW Cancer Council gets set to push for broad-brimmed hats to replace baseball caps in uniforms across the state as Sydney endures an unprecedented heatwave with temperatures scheduled to climb into the mid 30s for the third consecutive day on Sunday.
It follows a move from the Cancer Council in Western Australia to make wide-brimmed hats compulsory for all high school students during lunchtime and while participating in sport, while in South Australia the council has also lobbied for stricter guidelines for all students and staff to wear bucket or broad-brimmed hats outside during the hottest months of the year.
Liz King, the Cancer Council's NSW skin cancer prevention manager, said NSW schools that didn't have hats as part of their uniform needed to introduce them.
"It's a real priority for the Cancer Council to reduce children's exposure to UV particularly in those first 15 years of life which will significantly reduce their chance of skin cancer," she said.
"We are trying to get baseball caps phased out and get them to wear broad-brimmed hats."
At St Oliver's Catholic Primary School in Harris Park students were kept indoors on Friday as the mercury nudged 43 degrees in Sydney's west.
Principal Barbara Young said hat protection had become a natural part of her students' routine.
"It is so important with our Australian sun for it to be instilled in children," she said. "It's just a given; they know to wear their hats."
She said any parent "would love" for hats to be made compulsory in high school.
"But it is easier working with younger children to get them to say: 'yes I will wear my hat," she said. "With the older children that's harder to enforce."