Sustainable classrooms: mud walls, rainwater and visits from lizards

'It's learning-by-living rather than chalk-and-talk' - Matthew Jenkin explores the schools at the cutting edge of sustainability

Nestled among the swaying palms and lush jungle of Bali is an international school where children learn in bamboo pavilions and read from whiteboards made out of recycled car windows. The classrooms, which have no walls, are designed to help pupils feel more connected to their natural surroundings while studying a curriculum with an environmental twist. It has been hailed as the greenest school on Earth, but it is actually one of many adapting to the changing climate.

Green school Bali is the brainchild of John and Cynthia Hardy, who moved from North America to the Indonesian paradise in the 1970s. They sold their successful jewellery business in 2007 and used the profits to start a school that would pioneer sustainability in education. The couple had the idea after searching for a school for their children but being put off by the unimaginatively designed spaces and curriculums on offer.