It has played host to a giant helterskelter and a man-made sunrise but Tate Modern broke new boundaries when it was transformed into a campsite.

More than 120 children from all over Britain bedded down under canvas in the gallery's vast Turbine Hall for a educational sleepover.

The event was the culmination of a day-long consultation during which the pupils, aged between 14 and 17, were asked about the gallery's plans for the future.

Among the questions they were asked to consider was what should appear in the gallery's proposed extension, due to be completed in 2012.

Anne Cutler, head of education at the Tate, said: "Last year, 60 per cent of our visitors were under the age of 35. We need to generate a greater engagement with young people, particularly with the new building.

"We organised this day to ensure we did that properly rather than just pretend to."

Ms Cutler said she was impressed by the sophistication of the children's responses, which included suggestions to create interactive exhibits and galleries where unknown artists could display their work.

The highlight of the day for the children was being given their own tents and a set of paints with which to decorate them.

Emma Rhodes, 17, a pupil at Brockhill Park School in Hythe, Kent, said: "I was a bit sceptical a first. Camping isn't my thing but it's really wrapped up the whole experience perfectly.

"Today has been brilliant. I've been to the Tate Modern before but I'll now see it in a totally different light.

"I've learned so much about art and I think that the new extension will be fantastic, if they take our suggestions on board."

Abigail Otchere, 15, a pupil at Lilian Baylis technology college in Southwark, said: "I've never been camping before and I've never been to Tate Modern. I don't usually find galleries and museums that fun but today I've had a great time.

"If you think about the history of this place, having a sleepover here is pretty cool."

Staff were on guard to ensure the campers stayed in the Turbine Hall. The gallery opened as usual at 10am today.