Boys are too intimidated to sing during school music lessons because girls insist their voices are "rubbish" and "crap", new research has revealed.
And teachers often focus on songs outside boys' vocal range, meaning that the girls' description may not be too far from the truth.
Martin Ashley, of Edge Hill University, interviewed pupils at 17 primary and secondary schools about their attitudes towards singing lessons and school choirs.
He found that, from primary school onwards, girls held a genuine belief that boys were unable to sing. "Boys are rubbish at singing," one girl said. Another added: "Boys have got crap singing voices. They crack and break."
Previous research has shown that boys tend to intimidate girls during sports activities, insisting that the football pitch is their territory. But Dr Ashley believes that girls do the same during singing lessons.
"They poke me if I start singing in assembly," one boy said. Others said that girls stared at them or mocked them. "They gang up against us," another boy added.
The girls' belief in boys' lack of singing ability was so firmly ingrained that they gasped in amazement when played examples of high-quality singing by teenage-boy recording artists.
And a 13-year-old chorister and member of a teenage boyband described how he had learnt to be wary of younger girls. "It's some of the primary school girls who are laughing the most," he said.
Girls his own age were more easily impressed, although not necessarily by his singing ability. "I think he looks cute," one girl said. "It's a really nice, sexy image, and the clothes are lush," another added.
But their choice of language was revealing: boys who sang were "cute", "sweet" children rather than grown men. One boy reflected: "We don't want to be cute. We can't sing like men, so the answer is not to sing, or maybe to sing rap."
Dr Ashley describes a music lesson at a secondary school in which a Year 8 class was given a song pitched for adolescent girls. The boys struggled to hit the right notes and this was met by laughter and derision from the girls. "Most boys cannot take it," Dr Ashley said. "They respond with macho posturing, and drop out of singing altogether, on the pretext that it's girly."
By contrast, he cites the example of another secondary with a 100-strong boys-only choir. Here, songs were chosen to suit the adolescent boys' voices. "We're manly men in this choir," one boy commented.
Dr Ashley concludes that boys' perceptions of singing often depends on the teacher's ability to cater for their voices.