Schools are failing to teach children to be green and are treating environmental awareness as a peripheral issue, Ofsted has found.

Inspectors said that the majority of schools they visited did not pay enough attention to sustainable development. “Ethical purchasing was usually confined to buying Fairtrade products for the staff room,” its report on schools and sustainability said. The report praised schools for their imaginative projects and excellent teaching on sustainability, but it said that work tended to be uncoordinated.

Primary schools were better than secondary schools at putting children's passion for being environmentally friendly to good use.

Christine Blower, from the National Union of Teachers, said: “Far too few schools are teaching about the biggest issue facing the planet. Schools are over-burdened with a range of excessive and unreasonable external demands. This makes it harder to focus on teaching climate change and sustainability.”

Ofsted recommended that the Government should give higher priority to sustainability in schools, support this through funding, and ensure that the curriculum reflected the importance of the subject.

The Government wants all schools to become sustainable by 2020, as part of its ambitious £45billion Building Schools for the Future programme, which will rebuild or refurbish all schools in the country.

Schools are responsible for 2 per cent of all carbon emissions in this country - and almost 15 per cent of those produced by thepublic sector in Britain.

The Government has admitted that it would be too expensive to make schools “zero carbon”, in response to a committee of MPswhoasked for details about the environmental targets that BSF schools would reach.

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