The maths and English targets, on which the Secretary of State for Education and Employment, David Blunkett, has staked his job, will require "substantial" extra funding if they are to succeed, heads say.
The findings come on the same day as another survey says that primary teachers want more time to spend on literacy and numeracy. The study, carried out for the National Association of Schoolmasters-Union of Women Teachers, shows that more than three-quarters of teachers feel the National Curriculum for primaries is overcrowded, while the vast majority want more time to concentrate on basic skills.
Of 1,037 heads questioned in the first survey, almost two-thirds believe plans to ensure that 80 per cent of 11-year-olds are reaching acceptable standards in English by the end of this Parliament will founder without more money. Another quarter are still uncertain whether success is possible.
Almost as many believe the target of 75 per cent of the age group being on track in maths is unrealistic.
The doubts expressed in the study, conducted for the National Association of Head Teachers and the BBC education programme Just One Chance, prompted Mr Blunkett to renew his pledge to resign if the goals are not met within a five-year timetable.
But heads had failed to understand the size of the Government's investment in schools, he told the programme - broadcast tonight.Reuse content