In a survey by the Australian Council for Educational Research of 6,000 students in 400 primary and secondary schools across the country, researchers found that children who did not fit the traditional image of male and female were often harassed.
The report, Gender and school education in Australia, found that more than 90 per cent of children said sex-based teasing was a fact of life and 50 per cent reported being sexually harassed. Boys were overwhelmingly the perpetrators in the case of physical harassment. But girls were subject to verbal abuse by their female peers, and by boys, if they did not show physical skills.
Girls who dressed in a stereotypically feminine way could also be ridiculed. One girl in the final year of primary school said: "You have to be skinny and popular really, and not wear frilly dresses or pink."
Despite efforts to overcome sex stereotyping in the classroom, the study found that students were still reluctant to challenge typical gender roles. When given the option, many refuse to choose subjects traditionally perceived to be the domain of the opposite sex.
One outcome is that by the time they go to university, girls still opt for the "typically" female fields such as the humanities and health sciences. In the arts, humanities and social sciences, females outnumber males by more than two to one.
Meanwhile, males dominate business, science and engineering - in the latter case by a factor of more than six to one.
This situation looks set to remain for quite some time. According to the survey, in co-educational secondary schools, 60 per cent of boys said they would not take subjects that were usually taken by girls.
"If a boy did sewing, I reckon he'd get tagged as a fag for about a week, " said a senior secondary boy.
Girls, however, tended to be more adventurous, with 50 per cent reporting that they were prepared to try subjects that were traditionally taken by boys.
The researchers said the study showed teachers needed to try harder to free students from sexual typecasting. Boys and girls had to be encouraged to try different areas of study so that they became "more rounded human beings", it said.