Louise Walsh, a Welsh boxer and author of the book Fighting Pretty, said that Boxercise - a non-contact sport using punchbags and aerobic exercises - should be on the national curriculum for girls with aggressive tendencies.
But TES Cymru has learnt that some schools are already offering full- contact boxing to girls in lessons taken alongside boys.
Ms Walsh's remarks followed comments by Joe Calzaghe, Wales's unbeaten WBC super middleweight champion, who said boxing should be reintroduced into schools.
He told Boxing News that it could help curb boys' aggression, as well as keep them fit.
Ms Walsh said girls could similarly benefit from the discipline, albeit without the physical contact.
"There is a big difference between fitness techniques and full contact boxing," she said. "It is great exercise and teaches a certain level of discipline."
According to the National Behaviour and Attendance Review report, the largest investigation into behavioural problems of young people in Wales, which was published last spring, girls' behaviour is worsening as girl gangs become more common. The percentage of girls excluded from schools for violence in Wales is also on the rise, and they are getting into trouble at an earlier age.
Boxing is rising in popularity after a 1960s campaign to ban it from schools. Two years ago Monmouth Comprehensive set up an after-school boxing club to help tackle the poor behaviour of some pupils.
Around 50 boys and seven girls take part in intensive sessions. They cannot participate in full-contact sparring at school, but several have started fighting competitively at a local club.
Andy Williams, Monmouth's deputy head, is keen to install a boxing ring, but is unsure about the response. "It really has turned lots of young people's behaviour around. It is an incredible change from, for example, taking drugs or nearly being excluded," he said.
But Peter McCabe, chief executive of Headway, a brain injury charity, said health risks were high. "While it may be argued that children would be involved in non-contact exercises," he said, "the likelihood is that many of them will go on to take part in full-contact boxing outside of the school environment in boxing clubs or, worse still, with their friends without any supervision."
The British Medical Association has recently called for a ban on boxing for under-16s. But Carl Pesticcio, schools and youth chairman of the Welsh Amateur Boxing Association, said the rules for young participants were very strict.
"We are trying to encourage schools to take part, but to coach boxing you need to be qualified. Realistically, schools have to train their own PE teachers and it's difficult to get teachers to give up their own time."
David Thomas, a maths teacher at Willows High School in Cardiff and a keen boxer, has set up a daily after-school boxing club for pupils.
He recently gained a coaching qualification and is passionate about the benefits of the sport for pupils. "It doesn't encourage them to go out bashing people," he said. "They take out a lot of their aggression on the bags and pads. They've also started to pay more attention to what they eat and their health."
Should schools be promoting boxing to tackle rising aggression issues? Have your say on a special forum on our website: www.tes.co.ukcymru.