The shadow education secretary will claim the Conservatives are considering extending vouchers to schools, introducing a national funding formula and forcing schools to opt out.

Education and Employment Secretary Gillian Shephard and Liberal Democrat education spokesman Don Foster are also scheduled to speak at the conference.

Mrs Shephard is due to speak today in the wake of reports that the Tories are considering plans to allow parents and teachers to set up new schools with state funding.

Mr Blunkett is expected to use the platform in Sheffield to attack the Tories’ 18-year record and warn of the dangers of a fifth term. He predicts that the prime minister will take on board policies promoted by right wing ideologues in the Downing Street policy unit and others outside. The Prime Minister is expected to again press for the expansion of grammar schools.

Delegates at the conference in Sheffield, for the most part local education authority representatives, will also be told that the Prime Minister is still considering ways to make all schools opt out.

Mr Blunkett promises to forge greater links with teachers and local authorities to raise standards. He will also criticise the Government’s plans to introduce a national funding formula. This, he says, will take Pounds 600 million out of education.

He will tell delegates that since 1992 the number of pupils in classes of 30 or more has increased by half a million. Labour plans to limit classes for children aged 5,6 and 7 to 30 by using money saved from scrapping the Assisted Places Scheme. He will unveil a new plan to train teachers in new technology.

Don Foster is expected to challenge the Labour party on funding, he will also call for schools to be made responsible for every child they exclude and for appropriate deductions to funding to be made in full. He also wants excluded children to be protected by anonymity. “It cannot be right that children involved in exclusion battles appear on The Big Breakfast,” he said.