It is responsible for ensuring that millions of children learn to read and write properly. But the Department for Education and Skills stood accused yesterday of crimes against the English language.

Three leading writers - playwright Simon Gray, biographer Selina Hastings and poet Anthony Thwaite - expressed disgust at the "bad grammar, pretentious barbarisms and vulgarisms" in the Whitehall department's own guide to teaching English to teenagers.

They were asked by the Royal Society of Literature to judge the handbook, Framework for Teaching English: Years 7, 8 and 9 (ages 11 to 14) .

A typical paragraph of the guide reads: "Support is focused in the core subjects of English, mathematics and science together with other language-rich subjects as humanities and R.E.

"Departments have to bid in for support, making clear their commitment to the work and nature of development required."

Mr Gray and Mr Thwaite gave no points at all for the writing style while Ms Hastings took pity and gave the DfES 30 per cent.

Mr Thwaite said he was dismayed by the "bad grammar, pretentious barbarisms and vulgarisms which sound like stuff produced by third-rate advertising copywriters". He asked: "How can children learn clarity and elegance of expression if their teachers think this is the way to write?"

Ms Hastings said the reliance on jargon was "not only unpleasing to the ear but tends to obscure the sense", branding the guide "an ugly piece of prose".

Mr Gray said the document was impossible to understand. "I have now read it a number of times and find myself unable to mark it as I simply don't understand it," he said.

A DfES spokeswoman defended the guide. She said: "We are committed to excellence and clarity in the use of the English language, and follow the Plain English Campaign guidelines in our public communications."

EXCERPTS FROM THE GUIDE

* English teachers have a leading role in providing pupils with the knowledge, skills and understanding they need to read, write, speak and listen effectively but this document also addresses other subject staff. Language is the prime medium through which pupils learn and express themselves...

* Progression is defined by the Framework as a planned increase or refinement of skills, understanding and knowledge, and not simply progressing through the pages of set texts ... The teaching of texts is informed by objectives, and the challenge is to match texts and objectives at the planning stage...

* Teachers can meet some of these needs by differentiating tasks, offering personal support, targeting higher order questions, building in challenging open-ended tasks, and directing supplementary study outside the lesson... The focus of this guidance is on the way teachers can stimulate and direct the able reader or writer in everyday lessons.