Summerhill's reputation tends to precede it. The progressive boarding school in Suffolk, founded by AS Neill in the 1920s, may only have 80 pupils, but is as well known as Eton or Harrow, which it resembles in not the slightest detail. It labels itself "the school where kids have freedom to be themselves", which hardly sounds radical. Most, though, know it better as "the school where children don't have to go to lessons". Or, "the school with no rules".
With lessons, the cap fits, acknowledges Zoe Readhead, the principal, though it's a bit more complicated than it sounds. As for rules, I can almost see her blood boiling. As we walk through the school dining hall, she unhooks a pink file hanging from a noticeboard. "Here," she says firmly, as if presenting the Holy Grail, "is the rulebook."
And a thick volume it is. It contains 172 rules. There is even a list of suggested fines for miscreants: £5 for smoking, 50p for spitting on the tarmac, and £2 for graffiti anywhere else than the designated graffiti wall.
It is how these rules are set that makes Summerhill stand out. All have been agreed at the regular school council meetings where teachers and pupils each have one vote. Though the 14 full and part-time staff are outnumbered, it is this school council that makes the decisions about what goes on at Summerhill.
For all our enthusiasm democracy, we see the principle as essentially an adult thing. When AS Neill applied it to children, it caused great controversy – and continues to do so more than 80 years later.
"My view is that we have been pilloried," says Redhead, who is the daughter of AS Neill. "We feel constantly under invasion from the outside by people who don't seem to take that step to understand what Summerhill is about."
Because? "Because it challenges almost everything that people learn about children and childhood. Summerhill lets children take emotional and physical risks. It trusts children to make decisions. It gives children the right to talk to adults in the way they want. And that, I'm afraid, is frightening because people know that children should be seen and not heard. There is an expectation that children will follow a certain course, learn a set number of things, and will achieve academically and therefore be happy. Even though we know that that's not true, we stick with it because we believe there are no alternatives."
Summerhill has been given the perfect opportunity to nail its colours to the mast in an eponymous four-part drama series for the BBC's children's channel, CBBC, also to be shown on BBC1 and as a single feature-length episode on BBC4. The film is based on the school's courtroom fight to defend its particular ethos against Ofsted, which in 1999 filed a formal "notice of complaint" against Summerhill in an apparent effort to close it down.
At dispute was, inevitably, not requiring pupils to attend lessons. That was just too much for an inspectorate with rather more conventional views on children and childhood. The matter ended up before an independent schools' tribunal, which, encouraged by placard-waving current Summerhillians, eventually found in the school's favour. David slayed Goliath. Or, as the drama presents it, Peter Pan and his army of feisty youngsters vanquished Captain Hook and the baddies – Ofsted, their barrister, sceptical parents, and the rest of the world.
It's all bright colours, dazzling sunshine and happy endings. But how far is it an accurate portrait? The drama only presents Summerhill's successes – in its court battle and in bringing the best out of needy children. Readhead confirms that there are children for whom Summerhill doesn't work and who have to leave.
Quite a lot of the filming took place on the Summerhill site, on the outskirts of the market town of Leiston. Some current pupils feature as extras. But that was all back when it was sunny and warm. A wet Tuesday in January is perhaps not the best time to check out whether reality and drama coincide. "On a bleak January day with the east wind blowing," warns the school brochure (alongside pictures of ex-Summerhillians actors Rebecca de Mornay and Jake Weber, and artists Ishbel McWhirter and Evelyn Williams), "things are sometimes not wonderful."
In the film, new arrivals Maddy, broken by being forced to sit endless exams by her uptight mother, and Ryan, all but abandoned by his feckless dad after being chucked out of other schools, find healing and happiness in the parent-free Neverland. In today's weather, though, they would simply drown.
Readhead guides me into the classrooms. In Class 2, the Canadian teacher, Leonard, is sitting with Evie, 10, looking through history books so that they can decide what period she would like to study. Do they follow the national curriculum? No, says Readhead, as if it's the silliest question she's heard for a long time. "Obviously, if they are doing GCSEs, we follow the curriculum, but otherwise, no."
Another boy is on the computer, investigating fighter bombers. Two Japanese girls – Summerhill attracts about 50 per cent of pupils from overseas, many from Asia where Neill's ideas are held in high regard – are working on a translation of a novel from English into Japanese. Or perhaps it is the other way round. They are too engrossed to talk. And this being Summerhill, no one is going to make them. Quite rightly.
In the adjoining book-lined snug, another girl is lying on the sofa, reading. A classmate is asleep on the beanbag, Roald Dahl's Danny The Champion of the World open on his lap.
"We do what we want to do," says Chae-Eun Park, 16, from South Korea, who has been at Summerhill since she was eight. She has a small part in the film, chairing one of Summerhill's school meetings in the great entrance hall. Chae-Eun is completing her GCSEs and plans to do A-levels in London. (Summerhill takes children from five to 17, up to GCSE.) "People get very confused about what Summerhill's about," she says. "Even members of my family say to me, 'make sure you work hard', but there is no pressure at Summerhill. We have fun. We learn from each other and we learn to be with people. We make choices for ourselves, not because adults are telling us what to do. Having space to do what you like teaches you confidence and responsibility."
Despite its image as the school where children run wild, lessons at Summerhill are popular. The school's exam results are impressive. Even Ofsted, on a visit at the end of last year, managed to sing its praises. There is, in that sense, something reassuringly familiar about Summerhill, once you get through the gates and behind the caricature. It's warm. It's all about learning. And it's all about children.
And parents? The BBC drama portrays the school as keen to keep parents away to give children space to follow their instincts. Readhead believes that, despite their best intentions, parents can be obstacles. "Parents are less important in our children's development than we think we are," she says. "Yes, children need grown-ups, but they need other kids more. That's what we can give them here."
She quotes, as illustration, her own grandchild, who started at Summerhill recently as a day pupil, but was soon keen to become a boarder. She was having so much fun at Summerhill with her peers, Readhead says, why would she want to go home? It is pure AS Neill. "The function of the child is to live his own life," he wrote, "not the life that his anxious parents think he should live."
I can't decide whether my reservations about this sidelining of parents (other than as the people who write the £12,000-a-year cheque for the fees) is just my problem about being made redundant, or evidence of a well-intentioned but misplaced dogmatism. Certainly, the policy sits slightly oddly on Readhead's lips, as she was born in the school building, educated at Summerhill with her parents on hand, returned in the Seventies after her father's death to help her mother keep the school going, took over as principal in 1986, and educated her own children here. Some are now on the teaching staff, with their children as pupils.
But Neill's thoughts on education never appealed to more than a minority. There are a handful of schools inspired by his ideals in Japan, the US, Poland, Israel and Russia, plus a day school in Devon. Summerhill represents, arguably, the purest manifestation of his philosophy.
But that philosophy, albeit watered-down, has had a wider influence. "He has inspired ideas like school councils," says Readhead, "though it amuses me when they are presented as new ideas. We all yawn and go, 'been doing that since 1921'."
Her enthusiasm, though, is undiminshed. She recently took part, along with an old Summerhillian, in a workshop in East London. "I gave the kids roles and staged one of our school meetings. One said, 'I think we should have longer playtimes'. Another said, 'I think we should have playtimes between every lesson'. And the ex-pupil who was with me said, to get them going, 'Why don't you propose that you don't have to go to lessons?' Then one boy put his hand up and said he was on his school council. 'If I did that,' he told us, 'they'd chuck me out'.
It was so sad – a primary age kid who, if he made a proposal like that, would get chucked out. What does that say about his chance of being a good democratic citizen?"
'Summerhill' continues on BBC 1 today at 4.30pm and on CBBC on 28 January at 6pm. A full-length version of the film will be on BBC 4 on 28 January at 9pm