The recruitment crisis showed no signs of abating this week despite new figures showing that the teaching force has grown in the past two years.

Headteachers in the north London borough of Barnet sent a letter to every parent, warning of the threat to standards from staff shortages. Some schools are desperately trying to fill up to eight teaching posts before term starts in January.

The news came as it emerged that last week Tony Blair held a meeting with key officials from the Department for Education and Employment, the Office for Standards in Education and the Teacher Training Agency to discuss the problem.

Ian Penman, chairman of supply agency, TimePlan, said he was optimistic that schools would not have to move to a four-day week. However, he warned, “What is very concerning is the fact that Barnet is in no sense an inner-city authority. It is a relatively affluent middle-class area and if this is starting to hammer hard in Barnet, then nowhere is safe.”

However, while recognising that there is a shortage the Government said that things were starting to improve. Schools minister Estelle Morris welcomed official statistics that show Labour has increased the number of teachers in English and Welsh schools by 7,400 since 1998. She said that this reversed the decline of the previous eight years. She said that with classroom teachers now able to earn up to pound;30,000 a year there has “never been a bette time to join the teaching profession”.

The Government’s charm offensive in staffrooms was again evident as ministers promised to reduce the amount of time teachers spend on bureaucracy by 4.5 million hours - equivalent to three minutes per day per teacher.

However, ministers’ good intentions cut little ice with Tory leader William Hague who pointed to rising class sizes and said Labour had spent less of the nation’s wealth on education than the Conservatives did.

Mr Hague made his remarks in an education policy pamphlet. But his plans to scrap local education authorities and have “free schools” that would set their own admissions policies were deemed unworkable by heads and teachers’ leaders.

And he was not the only figure to propose controversial changes this week. David Hargreaves, chief executive of the Qualifications and Curriculum Authority, said that the GCSE could soon become a thing of the past. Mr Hargreaves said the exam had been designed as a school-leaving certificate but that with more young people staying on a more flexible approach was now needed.

Meanwhile in Scotland, parents have been banned from taking pictures of their children in the school nativity play. Perth and Kinross Council acted after being warned that taking pictures could breach rights to privacy under the Human Rights Act.

The ban was prompted by complaints from some parents who feared that films could fall into the hands of paedophiles. However, the council admitted that it has no powers to enforce the ban.