Quiet concentration characterises the scene at Bonaly Outdoor Centre on the outskirts of Edinburgh, where the suburbs give way to the Pentland Hills and the bypass cuts a visual boundary between city and country.
Ten children aged nine to 16 are learning an array of circus skills. One is walking on stilts, others are riding unicycles; a girl balances on a tightrope two feet above the ground, another on a ball, and a boy swings from a static trapeze. One girl is skipping - on stilts.
For eight days, the centre is home to Albert and Friends, London's leading youth circus training team. It is the organisation's 12th year performing at the Fringe, in the Royal Botanic Garden, but only its second offering circus skills workshops as part of the Fringe's bill of fare for children.
Albert and Friends began in 1983 as a voluntary youth organisation and has evolved to become charity. Children have come from Glasgow, Aberdeen, Preston and the Borders for the day, as well as local youngsters.
"We're hoping long term to develop this into a proper residential circus camp," explains Ian Scott Owens, otherwise known as Albert. "Children find it hard to assess risk because they're never exposed to it. We teach them how to fall properly. We do a lot of outreach work with schools. We have one school in London where pupils are learning circus skills as part of their PE. I label it as an intellectual physical activity: they really have to think."
Since 1999, Albert and Friends has delivered outreach workshops for disadvantaged young people in deprived estates in West London. Owens says circus skills enable children and young people to develop co-ordination and balance while developing personal and social skills and self-confidence.
The organisation teaches 400 children a week in London.
"It's way more fun than I was expecting," says Alessandra Quincey, 11, from Buckinghamshire, who is in Edinburgh while her mother is performing in the Fringe.
Nicola Titterington, a teacher at George Watson's College in Edinburgh, is watching as her sons, Guy, 13, and Rupert, 11. "I saw it in the Fringe programme," she says. "It's a bit different and it's nice that they can take part and learn something.
"I loved the whole experience," says Guy, a diabolo and juggling aficionado. "I learned some more tricks and it was great fun."
At pound;35 per child, including lunch, that is no doubt something of a relief to his mother.