Anyone who wants to see the director of Edinburgh International Science Festival walk on hot coals should make their way to Princes Street Gardens this April.

“The first time I tried it, I made a mistake,” says Simon Gage. “I did it on the beach at St Andrews. Sand isn’t firm enough, so you sink in and the coals wrap around the top of your feet. But I’ve figured it out since. It generally works fine.”

Walking on hot coals illustrates many of the qualities of events at the festival. It is participative, since anyone who buys a ticket can have a go. It’s unusual, it’s interesting and it stimulates thought.

“We explain the science that makes walking on hot coals possible,” says Dr Gage. “It’s not mind over matter - apart from plucking up the courage to try.”

But in one respect, hot-coal walking differs from almost all festival events. It is adults only.

“Our aim is to present science, to adults and children, as part of mainstream culture that can be enjoyed by everyone,” says Dr Gage. “We want going to a science festival to be as pleasant and easy as a book- reading or a film.”

Experiences at a science festival are more varied, however, with this year’s themes including art and science, the aesthetics of movement, earth and environment, and food for thought - in which “people are served a fantastic five-course meal, with a difference”.

In big cities around the world, diners are being offered a new experience in eating out - “sensory dining”, in which perceptions are deliberately altered.

“What we see affects what we taste,” says Dr Gage. “So you might be blindfolded. Or the colours could be changed. Even the shape of the plate can make a difference.

“Each course at this new event - structured by scientists, linguists and food buffs - will be a different experiment on how we experience what we eat.”

While the philosophy of giving people a fascinating taste of real science is unchanged, the methods at the festival are developing all the time, says Dr Gage. “We’re now looking closely at how people interact with us and aiming to make that easier.”

A deputy festival director, Amanda Tyndall, was recently appointed with that responsibility, he says. “We’re introducing a greater variety of styles and activities and more non-science voices. We’re using literature, music, art, comedy and film.”

Dance and testosterone, for instance, are interesting topics separately, but bringing them together can create an event that appeals to all. “It’s part of InMotion, a set of activities around human movement in sport, technology and dance,” says Dr Gage.

“We’ve teamed up with Dr Peter Lovatt, who’s interested in how well people dance as they grow older. He looks in particular at a phenomenon called Dad Dancing. It’s what you do when you get to middle-age and wobble around inelegantly on the dance floor.”

Dr Lovatt’s research suggests that how well men dance, as they age, is influenced by the level of testosterone in their bodies. So a mass- participation experiment at the festival will see volunteers dancing, being filmed anonymously, then judged by audiences on the appeal of their dancing.

“We’ll then look at how well that correlates with their level of testosterone, by measuring the relative lengths of their ring and index fingers, which is quite a good proxy for testosterone level.”

InMotion has an associated workshop on robot motion, which is currently touring schools as part of Generation Science (see panel), and will return to the capital for the festival in April. So too does another new event this year, the Speed of Light, says Dr Gage.

“This is an amazing piece of public art on Arthur’s Seat, with 500 runners clad in special suits covered with lights, running on electricity generated by motion and controlled remotely to create coloured patterns on the hillside.”

Other new events include Invisible Worlds - an “impressive, rather wonderful” photography exhibition of science, which has already started.

Unhappy experiences with school science can make some people reluctant to attend science events, says Dr Gage. “Our aim is to show that science is not at all scary. It is fascinating and enjoyable,” he says. “The secret is to use familiar locations and ordinary language to reveal the extraordinary.”

GOING PLACES: WORKSHOPS

Make a Move (age 7-plus)

National Museum of Scotland

Linked with InMotion, this takes a close look at how scientists are using new robot technologies in artificial limbs. “Using mechanical hands, pupils explore the anatomy of limbs, how they are controlled and how machines mimic human movement.”

Power from the People (age 7-plus)

National Museum of Scotland

This is a new, interactive workshop that explores the technology behind the Speed of Light event. Pupils work with dynamos and learn how to “generate enough energy to light the landscape”.

For the festival schools programme, Generation Science, which takes workshops into classrooms around Scotland, every year from January to May, call 0131 553 0321 or visit www.sciencefestival.co.ukeducationgeneration-science.