The Scottish Chamber Orchestra is having a very busy time. Its current educational development programme ranges from contemporary music for 15 musicians aged 60-plus in the Scottish Borders to work on some of the smallest islands of Orkney in preparation for the St Magnus Festival in June. This involves creative music projects with nursery schools and a concert of 20 young fiddlers with the strings of the SCO.

Meanwhile, at Aberdeen’s Lemon Tree Theatre, rehearsals of Beast! have been going on for today’s show. Inspired by the 12th century Aberdeen Bestiary, it is a composition of song, poetry and slide images performed by 60 P6 children with nine SCO members.

In Edinburgh, members of the Parsons Green Primary choir sit spellbound on the floor as around the walls of the City Art Centre the world of Camelot unfolds. Claire Mulholland, of the Scottish Storytelling Centre, takes the children to the mythical realms of dragons and knights, witches and Merlin.

This gallery visit is part of a musical project involving four city school choirs with their peripatetic teachers of music, six members of the Scottish Chamber Orchestra and the composer of a special opus for them. As well as Parsons Green, the participating schools are Cramond Primary, Lorne Primary and St Mary’s RC Primary of East London Street.

The composer is Edward Harper, a reader in music at Edinburgh University. The opus, Music for King Arthur, is a choral piece for 190 children and a small orchestra. Among Mr Harper’s work is Lochinvar, commissioned by the Keynote Trust for Ayrshire secondary schools.

“After I was approached by Stephen Deazley, the education development director of the SCO, I went along to two of the schools and sat in on the choirs’ lessons,” he says. “This was crucial for gauging their range and tone quality, especially at the top.”

Before the June premi re, Mr Harper has to finish his opus and the four choirs, their teachers and the musicians have much work to do. As the music includes duets on two pianos, the teachers will join a percussionist and five members of the SCO brass section in playing.

At the City Art Centre, Mr Deazley and colleague Louise Martin introduce the children to the opening tableau. Soon they are singing the funeral music as a canon.

But Arthur is not dead: he lives on in stories. After “Arthur is Dead”, there follow four themes: Sir Galahad, Excalibur, America (Mark Twain’s A Yankee at the Court of King Arthur) and the Holy Grail. Each choir will sing its individual story before the final tableau.

Jane MacLeod, Christine Alison, Jeanette Matuszak and Linda Evans are Edinburgh’s four senior teachers of music. The Arthur project challenges them to teach the choirs music never heard before and to prepare them for a premi re. It is a tall order, but music like this is needed to show children and audiences what they can do.

Music for King Arthur will be performed on June 13 at the Usher Hall, Edinburgh. Mr Harper’s composition should then become a valuable resource for schools.

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