Sing it loud: The children raising the roof of the Royal Opera House

The Royal Opera House is inviting 200 schoolchildren on to its stage this weekend. It's all part of a groundbreaking plan to get pupils singing again.

This Saturday evening, nearly 200 primary school children will make their singing debut on the main stage of the Royal Opera House, performing a new choral work written by one of the country's leading composers.

On the Rim of the World is a complex and haunting piece about growing from childhood into adulthood, and the ground-breaking performance is sure to raise the concept of school singing to a whole new level. "This is the biggest, most ambitious thing the Royal Opera House's education department has ever taken on," says Kevin Rainey, the ROH's opera education manager. "It is literally like putting on a whole new production at the Opera House, except that we're having to rehearse 300 non-professionals instead of just six professionals.".........

The work's young director, Karen Gillingham, is at the sharp end of this. She has been given only a few days of full rehearsal to pull the 200 children, and the 100 Kent amateur adult singers who are also taking part, together. By noon on the second day, in a secondary school hall in Maidstone, the strain is telling. "Stand still," she shouts, standing on a chair and waving her hands above a heaving throng. "Stand still, stand still, stand still, stand still! Listen. I've said it five times. That means standing still with both your feet on the ground." She waits for the restless mass to settle. "I'm still smiling," she says, pointing at her face. "But it's cracking."

For the children, the concentration is demanding. It's half-term, it's lunchtime, the music is complicated and the stage directions are difficult to remember. Some are definitely flagging, although most understand what a big chance they are being offered. "It's quite special as we've been chosen out of thousands of people who wanted to do it," says Reece Graves, 10, from St Eanswythe's Church of England Primary School, in Folkestone. "Sometimes it's hard because they want you to do changes, but then you get it sorted and it becomes good again."

Paradoxically, this ambitious project is rooted in the decline of school music. Over the years, singing has fallen out of favour in schools, but now big efforts are being made to revive it. Under a new national Music Manifesto, the Government is pouring £332m into music education, including Sing Up, a campaign to get primary children singing and to train teachers how to do it.

Meanwhile, the education arm of the ROH, known as Royal Opera House Education, has been doing its bit by training primary-school teachers and running the Voices of the Future project, which promotes the enjoyment of singing and invests in a repertoire suited to young voices.

As part of this, the ROH recently joined with seven other opera companies, including Glyndebourne, the Welsh National Opera and Opera North, to commission a work written for young people, by Orlando Gough, who is well known for his ballet and choral works.

"We've been working with all 46 lead music teachers in Kent for some time under the Music Manifesto," Rainey says. "It's amazing how many teachers have been told when they were at school not to sing, and don't know how to use their voice. They're not familiar with singing at all, so they do things like choose the wrong songs – year-seven songs, say, for year-four voices.

"At the end of the first year, last July, we said to them, 'Who wants to be on the main stage of the Opera House in March 2009?'" he continues. "Eighteen schools applied and we chose seven, which we picked out for different reasons. The school heads had to be on board, for one thing." Since then, pupils have been learning the piece in their own schools, while local choirs have been rehearsing the adult parts.

The children have not been hand-picked. Each school has contributed its entire year-five class, so performers include many children with special needs and plenty of non-singers. Dorothy Driscoll, a lead music teacher for a group of primary schools in east Kent, says, "We've had a few surprises – children we didn't expect have really got into it. Quite a few children have seen a different side of themselves, and it has really boosted their confidence."

Most of the children have visited the Opera House to see a performance of Humperdinck's Hänsel und Gretel, so they know how huge the venue is, and working with the ROH Education team has been an eye-opener. The young directors and vocal tutors are outstandingly enthusiastic and demanding. Nothing less than the best will do, and the pupils quickly realise that they need to shape up. By the end of a hard morning, most have morphed from pale and lethargic into animated and zestful singers.

The children are appreciative. "I like it because we are getting to do so much singing, dancing and acting," says Amy Brown, nine, of The Craylands School in Swanscombe. "If they didn't tell us to be quiet, the rehearsals would be a disaster," says Meryem Ali, 10.

The Royal Opera House feels that the programme is working. "We want all schools to be singing schools," Rainey says. "We want to put singing back at the heart of what a school does. In Kent, thanks to our work, every primary school now has someone who is a confident singing coach."

Helen MacGregor, the primary music advisor for Kent, points out that there has been a lot of training leading up to this. "It's all been of such high quality," she says. "It has really improved the quality of singing."

North of Maidstone, in Thurrock, other school and college students have been helping to make the sets and costumes. "We've been working with groups of 10 or 20 young people who've had a chance to work alongside the Opera House," says Gabrielle Forster-Still, the education manager for Thurrock. "They've done make-up and all sorts of things. They made the carpet on the floor of the set. The local college, Thurrock and Basildon College, has been great. I don't know what we would have done without them."

On the Rim of the World will be produced by other groups of young people in due course, and the ROH hopes to build on its work with Kent's schoolchildren. When the curtain rises in Covent Garden on Saturday night, a major new marker will have been put down for what can happen when children learn to sing their hearts out.