A report prepared for Warwickshire County Council says an extra Pounds 30m a year is needed on top of its current Pounds 160m education budget.
The study was drawn up by a panel of headteachers who found that a major investment was needed to bring schools in line with the best practice outlined in the curriculum.
This would mean cutting primary classes to 26, increasing numbers of teachers and giving teachers more preparation time.
Warwickshire is one of the seven English counties with the lowest funding per child this year in the standard spending assessment.
County education officer Eric Wood said the study was intended to bring the cost of the national curriculum to public attention, at a time of stringent controls on education spending. "It is pie in the sky to imagine this could be achieved immediately, given the pressure on public spending it could only be gradually implemented over 10 years."