The finding emerged in a report by the Office for Standards in Education this week, which examined how a sample of 24 schools had coped with the national numeracy and literacy strategies.
Inspectors found that heads at several schools had faced resistance from teachers when they tried to introduce the two initiatives.
They said that the most effective heads "are not afraid to make difficult or unpopular decisions", and had encouraged frank, sometimes painful, discussions of their school's weaknesses.
Examples of unpopular moves by heads included making staff take account of government initiatives; reallocating roles; and revealing before-and-after test scores for everyone's classes at teachers' meetings.
The report concluded that heads could create a culture of improvement in literacy and numeracy in schools by:
* making a convincing case for the need to change;
* involving all staff;
* having detailed knowledge of the two strategies; and
* calling in outside support where needed.
"Strategies in Action" is at www.ofsted.gov.uk