The Office for Standards in Education (Ofsted) says Battersea Technology College in south London, set up as a showpiece establishment by Wandsworth council, must produce an action plan.
If the plan fails to satisfy John Patten, the Secretary of State for Education, he is empowered to send in a team to take over the school.
The former Battersea Park school was inspected by a 13-member team of inspectors last November. Their report, backed by Her Majesty's Inspectors, will be published by Ofsted next month. The college's governors will then have 40 days to respond.
The report comes three years after the council revealed plans to revamp the school, where one-third of pupils were leaving without any GCSEs, and five months after the college opened its doors to pupils for the first term.
Michael Clarke, the principal, joined the college just over a year ago, and has installed a new management team and replaced 50 per cent of the teachers.
A letter from the inspectors to the college governors says: 'The difficulties faced by the principal and the college have been noted, and the steps that have been taken already to improve the college have been taken into account. The Chief Inspector has considered all the evidence and agrees with the registered inspector that the college requires special measures.'
Donald Naismith, Wandsworth council's director of education, said: 'This only confirms the governors' view and the council's own appraisal of the areas in which the college needs to improve.
'The college was already working on a development plan agreed with the council's own inspectors, and these initiatives are being incorporated into the action plan being submitted to the Education Secretary. The report will be a valuable element in the drive for higher standards, but it would have been still more effective and helpful if the college had been given a greater chance to settle down after a period of such rapid change.'Reuse content