From the football pitch to the classroom, schools have worked hard to stamp out sexism. Girls are encouraged to take up woodwork and boys to strut their stuff in the kitchen.

But there is one place where stereotypes are still calling the tune: the music room.

Macho instruments such as the trombone, drums and electric guitar are the province of boys, while girls stick to the gentler tones of the flute, harp and violin.

Now education experts are asking why. They blame gender stereotyping by both teachers and parents, peer pressure and the fear of bullying and the size and shape of instruments.

The researchers at the University of London’s Institute of Education - led by Professor Susan Hallam, a former professional musician – looked at the instrument choices of nearly half a million children. They found that the vast majority of those for harp, flute, fife, piccolo, clarinet, oboe and violin were by girls, whereas boys were far more likely to play the electric guitar, bass guitar, tuba and trombone.

They suggest setting up single-sex ensembles to bridge the divide.

However, the researchers admit that boys seem to like instruments that require physical input and are easy to learn, and girls seem to prefer gentler sounds – and instruments that are not too heavy to carry.

The report, in the International Journal of Music Education, said: “The cultural gender stereotyping of instruments inevitably has an impact on the preferences of boys and girls, leading to girls typically preferring to play smaller, higher-pitched instruments.”

A child’s choice of instrument can be heavily influenced by his or her music teacher. “Presenting instruments aurally and visually, without players, can encourage boys to select more feminine instruments, although it has little effect on girls’ choices.

“Changing the gender of the role model playing the instrument has also been shown to be effective with children aged 5 to 7. When a female is playing a ‘masculine’ instrument, more girls opt for playing it.

“Where children choose to play an instrument that is considered gender-inappropriate, they may experience bullying or loss of popularity,” the report added. “Even where there is apparently free choice, stereotypical views of masculinity and femininity still play an important part.”

The gender divide becomes more pronounced in secondary school.

“Social factors that may be important include role models, stereotypical expectations, culture, religion and parental influence,” the report said.

“Boys may prefer instruments that are struck or require high levels of physical exertion. The technical difficulty of the instrument and level of persistence required to play it may also play a part, as evidence indicates boys tend to do less practice than girls.

“However, for some children it may simply be an issue of access, cost and whether transport is available.”

The report said that music teachers should make it clear to pupils that they can learn any instrument.

Professor Hallam said: “The world would be a poorer place if James Galway had been discouraged from playing the flute and Evelyn Glennie had been told that girls shouldn’t become percussionists.”

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