In what sounds like the first episode of an off-beat Australian teen sit-com in which letters of appointment get crossed in the post “with hilarious consequences” as Radio Times might promise, one of our leading theatre directors is to become head of a Croydon comprehensive school next month.

Clare Venables thought some hideously irritating mistake had been made when, just as she was deep in the planning for a new and particularly complicated production of Kiss Me Kate last October, she was approached by a firm of head-hunters. She was a theatre director, she told them bluntly, not a headmistress.

“I didn’t think much of it, to be honest. Then I started to wonder how they had got on to me,” she says. “It was actually rather clever, because I started as an academic and over the past 10 years I’ve done more and more teaching [at RADA, the Guildhall School of Music and the Actors’ Centre which she co-founded] as well as running theatres and directing plays and opera.”

Her new charge is not just any suburban 720-pupil comprehensive, although it is that, too. It is the Performing Arts and Technology School, set up five years ago by the British Record Industry Trust and known, simply, as the Brit School.

Technically, the Brit is a City Technology College, but there is none other like it. The academic year is five eight-week terms split by two-week breaks and a four-week summer. The age range of pupils is 14 to 18. Its base is the whole of the performing arts and it was expected to be a Fame school, copied from the American model, but somehow it did not turn out that way.

“In most acting schools what you get is a teaching staff that hasn’t been very successful on the stage or screen, or people who have vast qualifications but no performance experience,” says the school’s chairman of governors, the film producer Lord Birkett. “We don’t want to be RADA or the Royal College of Music, we’re not a college or a training centre. We’re one school which has got to bring together both worlds, which has got to get its children through GCSE, A-level, BTechs, NVQs and whatever else is in the system. So we needed someone with a real flair for performance and as much flair for administration. ”

It took nine months to find Venables after the founding principal, Anne Rumney, who had been an inner-London comprehensive school head before setting up the Brit, took early retirement last year. “I think we probably always wanted someone from the performance industry as principal, but it was too much of a risk to start with one,” Birkett says. “Anne was the perfect choice five years ago, and Clare is the perfect choice now.”

Venables could have been made for the job. Apart from having a 17-year-old son, Joe, who seems destined for the film industry, both her parents were educationists. Her father was Sir Peter Venables who, with Harold Wilson and Jennie Lee, set up the Open University, a process Clare watched being opposed and even obstructed by her father’s one-time colleagues.

“It was all that ‘more would mean worse’, saying that it was going to dilute education so we were all going to end up like American morons, and Dad lost a lot of friends through it,” she recalls. “But it was funny how the phone began to ring again when the thing started to be a success.”

She went to Manchester University to study philosophy. “I wanted to solve the universe, I was going to be the first female Jean-Paul Sartre.”

But the degree was mixed with history of art and, for the first time in that university, drama. “They were making it up as they went along, really, but the minute I walked into a rehearsal room for the first time I knew that was what I wanted to do.”

She switched to drama at the end of the first year, graduated and went straight on to the teaching staff, specialising in Greek and Roman theatre, Brecht and Stanislavsky.

“I think that right from that first moment I had a sense that in a rehearsal room you have to deal with the great verities and very practical things simultaneously,” she says. “So if you’re singing a song you have to be able to understand and respond to the significance of the words and music, but you also have to sing it in tune. It’s the same with plays. If you’re doing Hamlet you’ll be discussing the meaning of existence one minute and the next discussing how to get a piece of furniture on and off stage without distracting anybody.

“It’s that combination, of really quite profound thinking with very practical things, that I believe the kids who respond to the performing arts are responding to.”

In 1967 she went to the Leicester Phoenix as an actress, set up a youth group there, and then set up and directed the mammoth young people’s project The Lincoln Mystery Cycle in Lincoln Cathedral for five years. She developed into a director and administrator, running such theatres as the Library Theatre, Manchester, and the Theatre Royal Stratford East in London. Then there were 10 blisteringly creative years as artistic director of the Sheffield Crucible. She left in 1991 to go freelance and try her hand at opera and music theatre, covering everything from Funny Girl to Don Giovanni.

Her Kiss Me Kate at the new Norwich Playhouse is a gloriously uninhibited dissection: “I’ve gutted it and put it back together again, I’ve mixed up opera singers with actors with dancers, and it’s been quite joyous. It’s a bit like a Marx Brothers film with music, good music.”

She will be the full-time principal of the Brit, though what that means is still a matter of interpretation. “We told her that if the Met in New York asks her to do Figaro she must certainly do it,” Birkett says. “The only condition would be that all the rehearsals should take place at the Brit School. I think she got the point.”

But she smiles when reminded of the remark, as if remembering a good joke. “I will not be doing anything else for a good while, certainly, but I’ve been asked to do an opera at the end of next year - in this country - and I haven’t said no yet. I will have to keep my hand in otherwise I’ll quickly get out of touch and the whole point of my being at the Brit School will be negated. ”

When we met she had only made a one-day visit to the school and seen a dance class, a theatre history class, a class painting sets for the production of a play and a small group learning television editing. The music room was not being used that day, but the equipment and facilities over the whole spectrum for dance music, acting and the support crafts and technologies, she says, were to die for - “it was like heaven”.

The truth about the Brit School is that the young people are chosen as much for their determination to go there as for their ability, and at the end of the school day they don’t want to go home. There is serious activity going on well into the evening.

“One has to be very careful not to stretch kids so far that they feel inadequate, but if you don’t stretch them they get very bored. So I hope over the years we will develop results both academically and practically,” Venables says.

“The board could tell I wasn’t happy with the idea of education for the sake of education, but the idea of getting excellence up to the level appropriate to the child is very important to me.” So she is pleased about a low pupil-staff ratio, and not bothered by a mediocre academic record so far and the idea of national tests and inspections.

She also found mutual concern between pupils and staff about, “the underlying seriousness of the structure, about wanting to learn the disciplines and values of the performing arts themselves but also to apply those disciplines and values to the way the school is run and to other learning”.

“All this has got to be tested,” she says, “and it’s testing my own view that if you’ve got a group of artists working well together it can be a little paradigm of how society can work - because you have to be entirely yourself otherwise you can’t create, but you have to be yourself in the context of everybody else being entirely themselves.”

Clare Venables has been appointed for her thorough knowledge of the business of performance and making it relate to an audience. “I would like the school to have a slightly higher profile and I hope Clare will bring all her famous friends here,” admits Lord Birkett, “but that isn’t why we have appointed her. I want more vigour in the school, and that is what I believe Clare will bring.”