There is a word that aspiring headteachers of the Nineties should hold in their minds and repeat like a mantra in the interview room: vision.
The first question will be: "What do you want to do for this school?" The required answer begins: "My vision for Grindthorpe High ..."
In the old days, a headteacher was like a despot - sometimes enlightened, sometimes not - in a small, independent state. Nowadays he - sometimes she, but usually not - is more like a football manager. Charisma, authority, even evangelism are essential qualities in the modern head. But if the school begins to slip down the league table, then his neck will be on the block.
Yesterday Gillian Shephard put the role of the headteacher at the centre of her education policy. A good head, she said, was the key to a successful school, and professional recognition would do much to raise standards in schools. Her plan for headteacher qualifications has won praise from across the political spectrum - not least from Labour, which announced an identical scheme four months ago.
But why is a head's role soimportant? As Mrs Shephard said, no enterprise can succeed without leadership, and research has shown time and time again that it is vital in education. A good headteacher inspires and motivates staff and pupils while keeping a firm eye on the school's ultimate goal: raising standards. School inspectors have found a strong link between failing schools and weak leadership.
The Government has already launched Headlamp, a scheme under which new heads are given pounds 2,500 to spend on the training of their choice. They may learn financial management, crisis management and the management of change, the curriculum and pastoral matters.
Such training has been on offer for 20 years but it has been patchy. Heads have attended courses at management centres and those organised by the Industrial Society. Some have even done MBAs to prove their management abilities.
Armed with these skills, new recruits must return to school to win over their staff. A prime example of vision and charisma going awry was set by Michael Clark, employed to improve Wandsworth's failing Battersea Technology College. Nothing if not evangelical, he departed in January after alienating staff by suggesting that they were either for him or against him.
The successful head will set an example to the school. Above all, he or she must be able to focus strongly on what matters most: on standards of teaching and learning. Five years ago it would have been unusual for a head to spend time watching staff work, but inspections and appraisals have changed that. Now the classroom door is never really closed.
But being a headteacher is not just about leading - it is also about inspiring. Here another fashionable word comes into play: empowerment. The best headteachers make their staff feel that they can have ideas of their own and that if they take calculated risks they will receive support.
A personal touch is important - something, according to Professor Michael Barber of London's Institute of Education, that women heads display more than men. One head he met sent a card to every former member of staff on their first day in a new job, saying: "Good luck and thanks for everything you did for us."
"People remember that kind of thing - it really matters," he says.
Being a head is not only about cards, however. There will be hard decisions to make. While the teachers will mutter in the staff room about one of their number who is lazy and incompetent, they will unite against the head who tries to have him or her replaced.
The first year or so will fly by in a whirl of new initiatives. While these will be in place by the second year, few improvements may yet be visible. This is the time when a good headteacher keeps faith, and constantly tells the rest of the school: "It will work. Give it time." It would be a very strong head, not to say a foolish one, who never had doubts. But the key to success is never to show them.
The staff will not be the only ones whose spirits need bolstering from time to time. In 1993 the Government gave school governors the role and duties of employers, and hence they now play a much bigger part in the running of the school than they used to. While some heads can wrap their governors round their fingers, others have more trouble. The Secondary Heads Association takes about six calls a day from headteachers worried about their relations with their governing body.
Heads today must perform a delicate balancing act at all times between the demands of staff, pupils, parents and governors. The demands of their spouses and children will generally take fifth and sixth place in their attentions - the job usually begins at around 7.45am and continues until nine or 10 at night, when the governors' meeting, parents' evening or school play finishes.
And although many headteachers talk of the occasional joys the job brings - the success of an initially unpromising pupil, the school production which goes without a hitch - more dwell upon its stresses and strains. Most heads now are appointed in their late thirties or early forties, and an increasing number are taking early retirement in their fifties on health grounds. Some of those who go are victims of "football manager syndrome", people's tendency to seek a scapegoat when things go wrong, but many have genuinely fallen ill through overwork.
So what can we do to make sure that good headteachers get even better? How can we give bad heads the kick-start they need to improve?
Yes, Mrs Shephard's courses will help aspiring heads to take advantage of training, but the profession is divided about them. While all welcome the principle that would-be heads should be better trained, some warn of the danger of expecting certificates from all. Governors could be lulled into a false sense of security, believing that any candidate with the qualification is fit to be a head, some say. But others believe it will be a starting point: without it, a deputy head will not even start down the rocky road to successful headship.
But the crunch time for many heads comes six or seven years after taking up a post. By this time the impetus of those first new initiatives has begun to slacken, and the flow of ideas may be becoming a little sluggish. Professor Barber suggests sabbaticals, which could allow them to refresh their ideas and to take a breather from the daily grind in school.
Ofsted, the schools inspection body, is already offering primary school headteachers the chance to spend a year on attachment to its teams of inspectors. This is certainly one way in which a head can pick up new ideas and judge his or her school's performance against that of others, although there are questions to be raised about whether it does anything for the quality of school inspections.
Another new initiative being mooted in London could also help. A group of heads is planning to set up an English version of the Principal Center at Harvard, in the United States, where heads can meet, take in-service courses and discuss the latest issues. Such networks could form a useful service: headship can be a lonely business.
While Labour and the Conservatives want training for heads, Labour also wants to provide more back-up. Under Labour, "super-teachers" would have leadership skills but would also provide an example of excellence in the staff room. And with better training for governors, the post of the head could become less arduous.
But there is a harder fact that most new heads must face: some of them will fail. And for those who do not recognise their own unsuitability and leave, there must be mechanisms to ease the passage out of office.
As one American commentator put it recently: "Ten years ago if I had a vision they would have locked me up. Now I can't get a job without one." Nor, in the brave new educational world of the Nineties, would he be able to keep one.
What makes a good headteacher?
Fay Weldon, author
She or he has to be a good manager - a chief executive rather than a leader. Headteachers have had to do so much form-filling and paperwork. She or he should be someone children look up to and respect who can teach them the ways of the world. A good headteacher is a good person!
Mary Warnock, former mistress of Girton College, Cambridge
Good judgement. They shouldn't do anything silly. Liking one's pupils is very important. My fault as headteacher was I liked my pupils very much and didn't like the other members of staff at all. I think one has to be very clear-headed and cool.
Will Carling, England rugby captain and management consultant
The ability to let each individual under his/her charge flourish. That means teachers and pupils.
David Smith, head of Bradford Grammar School
He has got to like children more than anything. That's about it. Let everybody else talk about dynamic leadership and management.
Rosanne Randle, head of Dame Alice Harpur School, Bedford
Vision. But it's no longer about inspirational leadership. Team leadership is what matters.
Tony Mooney, head of Rutlish, John Major's old school)
Patience, sense of humour and an understanding of people. They must keep up to date in developments in teaching and must talk to teachers and encourage them in what they're doing. He or she must be a critical friend.
Peter Hullah, head of Chetham's School of Music, Manchester
Someone who likes people and realises they are his greatest resource. Who is good at listening and understanding that people learn from their mistakes.
Ralph Ullman, head of Wellingborough College
Someone with a clear sense of direction who is good at persuading other people that the things you want them to do are the things they want to do.
Dr John Moore, head of King's School, Worcester
The ability to listen. To take decisions and to cope with the totally unexpected.
Chris Woodhead, Her Majesty's chief inspector of schools
A vision of the curriculum and a real personal sense of appropriate standards. The strength of personality and interpersonal skills needed to engage with teachers in raising standards. The drive to plan programmes of improvement and a sense of humour.
Louise Woolcock, first female joint head of school at Rugby
They need to be aware that their students are under pressures of academic work and extra-curricular activities. They should be approachable and should be good at promoting the school to present and prospective parents.
David Blunkett, shadow education secretary
A good headteacher has the skills of a leader, combined with an understanding of the feelings of an angry parent.
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