Institutions not meeting the target by 2011, a year earlier than planned, will be subject to a formal intervention. To back up the revised commitment the government is investing £200m in programmes such as the London Challenge scheme, which helps schools in disadvantaged areas, and its academies programme. In his Budget speech to Parliament the Chancellor, Alistair Darling, said: "We will extend the successful London Challenge model, enable the best head teachers to turn round low...