Discipline is the key to creating good musicians, Richard D North finds
Take 60 primary school children from Southwark - just across the river from Westminster, but a world away, too - and invite them to take an interest in a tune from Shostakovich's 7th Symphony (the Leningrad). Surely a recipe for disaster, or at best shuffling feet and those looks of ineffable boredom the young can hoist in minutes.

It is the run-up to National Orchestra Week, when the the classical world puts on its happiest smile, opens its arms wide, and hopes to make friends and dispel myths. If ever there was a time to help the whole family to realise or to remember that orchestras are very exciting animals, this is it. Most of the country's finest including the LSO - will be involved.

The children are in the concert hall at Morley College, the South London venue where the Russian composer rehearsed the debut of another piece with the London Symphony Orchestra 20 years ago. The youngsters don't seem all that impressed when they hear this resonant snippet of musical history.

Ian McDonough, who retails it, is a violinist and among several LSO players who are spending a February day working with Southwark's finest. Whatever the portents, something close to magic happens, as the distinguished musicians work in their unassuming way with the young. The aim is to make it possible for untrained 11-year-olds to compose and perform respectable orchestral - orchestrated, anyway - music in a bit over an hour. It's done by getting them to learn the tune, which is no harder than getting them to memorise Colonel Bogey. The animateurs then get them to name five different sorts of noise they could make: clapping, whistling, stamping, humming and more. Oh, and tapping, suggests somebody. "Oh, right - ostinato," says a workshop leader. "By the way, we'll use lots of Italian words. Musicians do. It's so orchestras can play anywhere in the world and understand instructions." Wallop: the idea of lingua franca is sympathetically planted.

At first the children are a little shy, but not for long. "At this age, they do seem quite open - even the boys," says Tom Deveson, Southwark's music adviser. The adults ask the kids how they could handle the tune differently, to make it less boring. "How about one group starting the tune, and then the other starting a little later?" asks one of those bright sparks whose hand just seems naturally to hurl itself into the air any time anyone asks anything. "Ah yes", says the animateur: "A canon."

Inside the hour, the children are knocking the tune around in fine style. It sounds defiant when they sing the words "We will fight for freedom", as in the mouths of Leningrad's beleaguered citizens. It was menacing but weary when it was crunched out from the heels of the Nazis. "Don't forget, they've walked all the way from Germany," a musician reminded them.

It was all surprisingly beautiful, but the animateurs could have done it without top-flight musicians. What the orchestra members contributed most was discipline - not brilliance, but orderly competence. When Nigel Broadbent, violinist, quite suddenly asked of one laggard, "What's you're name? Patricia? Well Patricia, we've got to get a little closer at the end", I heard the distant sound of whips being cracked.

And then Mark Withers, the senior workshop leader, interrupted a choral bit and said, "Now, we're finding out that quiet singing is one of the best sounds we can make. But some of you aren't singing and that's no good. It's everyone singing quietly which sounds great". They did, and it did. Things were a bit like that during the Royal Philharmonic's outing at the Royal College of Music that Sunday. When workshop leader Tim Steiner, more razorhead biker than obvious aesthete, called for quiet, it was with an air of menace which was very effective. "Someone's still rattling," he said. A mum and tot with a bottle of beans were duly mortified.

In a way, silence was the whole point. The important lesson was that the sudden halt of a crescendo was its most remembered feature: and the children got the hang of stopping together, letting the musical silence lap around a room where no one made any other noise. However, RPO played a different game from LSO's. There was a huge range of talents and talent in the young instrumentalists. Some had never played before, others looked like Suzuki veterans. "Andrew Davis is her pin-up," said the proud mother of Felicity Wake-Edwards, 7, whose gaze never wavered from Tim. This was a family so committed they had brought a string of llamas' toenails for a World Music effect.

"Let's play our A's,"calls Celeste Rush, a violinist for RPO, in the violin workshop. "Right, now our D's". A noise as of hornets is emitted. Each group is unaware that all the others in their separate workshops are building two or three noises which can be punched out on a beat, sustained, or varied, to order. In the violins' case, the sustained note doesn't even have to be on a particular string, yet the massed sound is quite nice. The more advanced children do a few beats of A and D, and the absolute beginners just plod on continuously with the D.

But all done to command. When we rejoin the hundred or so musicians in the main hall, Tim has marshalled a mighty percussion section, and augments it with choir, strings, woodwind. And there is a little brass section in which Rebecca Smith (7) on pocket trumpet, and Vincent Bardsley (9) on cornet, standing, are about as tall as their mentor, the RPO's principal trumpet, Ian Balmain sitting. When Tim points at them and makes the sign for the full-on tune version of what they've worked out, it's a tear-jerking moment. The resultant, exultant noise is funky, massive, raucous and tender by turns.

The RPO showed children what a combination of exuberance, co-operation and discipline can achieve. The LSO did that too. As Tom Deveson remarked, "Music is a wonderful combination of the left and the right hand parts of the brain at work." Emotion and maths in equal measure.

After a few more weeks' work in their schools with the LSO people, 180 children will walk into St George's Cathedral, Southwark and play their variations on a Theme by Shostakovich. What is more, they will go to the Barbican on March 6 and hear the "real" thing: the Seventh Symphony played by the LSO. And they will probably think it glorious. They will have by then thoroughly possessed the ditty, and when they hear it messed around and played with by the original composer, they will know what he sought to achieve.

National Orchestra Week, 9-15 March 1998 but some events go earlier. For local details call Talking Pages 0800 600900 and ask for the Association of British Orchestra's National Orchestra Week. The Royal Philharmonic will be holding a workshop at the Royal Albert Hall, on April 9. pounds 5 child, pounds 8 adult or pounds 18 family of four. Call 0171-589 8212 The primary school children of Southwark will perform at St George's Cathedral, Southwark, 16 March, 9.30am-11am. Info: Karen Irwin, LSO, 0171-588 1116