When Steve Kenning became head of Callington Community College in east Cornwall seven years ago, he found what he describes as "a very average comprehensive school". Around 50 per cent of pupils were achieving five A to C grades at GCSE, but aspirations were low. Numbers were beginning to decline, money was short and morale in school was poor. "There was simply not a lot happening," says Kenning.

When Steve Kenning became head of Callington Community College in east Cornwall seven years ago, he found what he describes as "a very average comprehensive school". Around 50 per cent of pupils were achieving five A to C grades at GCSE, but aspirations were low. Numbers were beginning to decline, money was short and morale in school was poor. "There was simply not a lot happening," says Kenning.

He was determined to change that. What he wanted was to transform the culture of the school into one of "can-do", where everyone felt valued and believed themselves capable of doing the things they wanted to do. "At first it was hard," Kenning says. "The place didn't want to change."

He brought in basic psychology training, for pupils and staff, to encourage them to believe in themselves and take more responsibility. He invested in professional development for staff and urged people to come up with ideas of their own. He streamlined the management structure, signed up for new initiatives and incorporated the conditions of the US-based Global Institute for Student Aspirations, emphasising creativity and curiosity, fun and excitement, and leadership and responsibility.

It was four years before there were any signs of progress. But now Callington is buoyant and oversubscribed. It has specialist sports status (and is applying for music as a second specialism), is a training school, a Leading Edge school and a Network Learning Community school. Exam results are well above average. "It's an exciting time in education, because schools are getting the chance to make decisions," says Kenning. "But you have to have a clear vision and have to take risks."

The scope of the head teacher to influence and shape a school is considerable, says Heather Du Quesnay, the chief executive of the National College for School Leadership, and the head's personal style is enormously important. "What effective heads do is bring their own unique style and character, but ensure that this interacts with the individual character of the school - so you get something very special," she says.

A new head should begin by winning over the staff and leadership team, she advises. "There may be people who are stuck in their ways, resistant to change, or even one or two who are downright blockers - and you have to find ways of coaxing them, bringing them along with you," she says. At times, a head may need to be "utterly ruthless" about moving people on in order to effect change, she says. "You have to have a burning sense of commitment and moral purpose about what you are doing for the children in your school: that is what keeps you going when things are difficult."

Steve Sanderson became head of St Joan of Arc Primary School in Bootle, Merseyside, 14 years ago, at a time of high unemployment in the area. The school buildings were dilapidated, the playground was strewn with rubble and morale was rock-bottom. "The first thing I did was build some consensus among the staff about how to raise aspirations," says Sanderson.

They began on the playground, involving parents and children, and picking up a Queen's Environment Award in the process. They moved on to the buildings and a new parents' room, and adult education classes were started (it is a pilot school for the Government's Schools in the Community programme). In the classroom, creative work in art and drama was combined with an insistence on basic skills in maths and English. Two new minibuses enabled pupils to get out and see what they were learning about, and links with schools in Belgium, Hungary and China expanded their horizons further.

It took eight to 10 years, according to Sanderson, but the "collective vision" of school and community has paid off. SATs results at key stage two are now 90 per cent and upwards and children talk for the first time of going to university. Sanderson stresses: "You have to be prepared to serve a community over an extended period of time. Some schools get disheartened and drop things because they haven't worked initially. But you have to dig in."

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