Obviously, they won't be frog-marched to the hairdressers, but they won't be getting back onto school property until the mullet is gone.
Waverley College in the Eastern Suburbs of the Australian capital city said that the hairstyle is 'not acceptable', despite the fact that it has enjoyed a rapid resurgence in recent times.
According to The Daily Telegraph, Waverley's deputy principal Patrick Brennan said: "The 'mullet' haircut trending at present is not acceptable and students will be directed to the local barber or their preferred hair stylist to rectify any issues."
A spokesperson for the school backed up her colleague's stance, saying in a released statement that the controversial haircut ban was necessary to teach their students that 'rules, guidelines, and expectations are necessary for growth'.
The spokesperson added: "So while personal expression, fun and creativity are important parts of who we all are as individuals, it needs to fit within the bounds of what is acceptable and required of us.
"Student hairstyles fit within this principle,"
As we've mentioned, the style has enjoyed something of a return to form after years spent as the laughing stock of the haircut world.
Celebs such as Miley Cyrus have even been spotted rocking the mullet, and London hairstylist Lulu Richards told BBC News: "Mullets used to be a negative term that people used to describe a haircut that had 'gone wrong'. Now it's my number one request,
"Clients from all backgrounds, ages, jobs and lifestyles are after one."
Strangely enough, this isn't the only school in Australia that has banned the mullet. A Perth school declared the haircut illegal back in June 2020, leading to accusations of 'class warfare' on the internet.
A letter to parents informing them of the school's decision was published on Reddit and was described as 'class warfare on school mullets'.
That letter stated that 'some year 8 boys recently presenting with a hairstyle that resembles a mullet.'
It continued: "Please note that this is seen as an extreme hairstyle and not in keeping with the personal presentation of a Mater Dei student.
"If your son currently has this style, please ensure this is rectified by the start of term."
Naturally, some people have accused the school of being overly restrictive, whereas others say that it is not unusual for private schools to regulate their pupils' appearance.