Pimlico School, the showpiece London comprehensive with 1,500 pupils, figures prominently in a dossier alleging political bias in schools which has been handed to Sir Keith Joseph, the education secretary.

A copy of the dossier, drawn up by Lady Olga Maitland, chairman of Women and Families for Defence, has been passed to The TES.

Much of the evidence is sketchy and anecdotal, necessary because children and parents are afraid to speak out publicly for fear of damaging their prospects at school, says Lady Maitland.

Few of the 13 case histories summarised in the dossier contain sufficient detail for a ready check on their authenticity, a task that Sir Keith has passed to his officials.

Pimlico is the exception, largely because Mr Timothy Evans, aged 19, who left school this summer after seven years as a pupil, has given a detailed account of how staff bring their own political views into the classroom, leading to a left-wing bias in the school.

This week he spoke to The TES, spelling out the message he has already given Sir Keith at a private meeting. He said that political indoctrination at Pimlico took two forms: a covert “cultural indoctrination” that manifested itself through teachers encouraging pupils to think of demonstrations against nuclear weapons as good things and spending cuts as bad things, for instance; and more overt propaganda in class or school assemblies.

In October 1982, a visiting theatre group put on a play about a group of British schoolchildren visiting Moscow. Mr Evans said the cast painted the picture of the children having a wonderful time in a contented society.

The audience enthusiastically stamped their feet to the strains of the Red Army choir singing the Internationale, he said.

A representative of the Inner London Education Authority said that Mr Bill Stubbs, the director of education, had ordered an inquiry into the allegations.