By Alison Smith
BBC News education reporter
Some of the children at the Acorn School believe they have found a second family.
Principal Graeme Whiting set up the school and wrote the curriculum
With just 120 pupils, everyone at the Gloucestershire school gets to know each other well.
There is no "sir" or "miss", no formal discipline procedures, no uniform - and no state exams.
The principal, Graeme Whiting, who says he has "old-fashioned values", can describe the interests of every child, and keeps in touch with former pupils.
The small school buildings look like the quintessential village primary which you enter by the back gate.
Inside there is a distinct lack of any stress about grades or fitting in with the crowd.
While other teenagers are worrying about A-levels, Nicole, Finn and Amelia, are researching their final year assessments.
The three are class 13. They have their own laptops, a small room to themselves and the freedom to study absolutely anything they choose.
Finn, 18, is studying Tibetan medicine. He will produce a project from his final year's work which he will illustrate and bind himself.
He says he would like to go to university but is in no hurry to decide what to study.
Despite having no A-levels and following a completely independent curriculum, many pupils do go on to university.
But there is a risk that an institution may simply dismiss an application which contains no GCSE or A-levels.
Richard, 19, who is studying outdoor environmental education at Liverpool John Moores University, has returned in a lecture-free week to catch up with old friends.
To get his place he had to sell himself a little more by personally talking to admissions tutors about his work.
The only drawback of his schooling was that he was less well prepared for revision and sitting more formal exams.
Nicole, who is studying human physiology, describes year 13 as "a foundation into university".
"We're not getting fed anything by teachers. This is completely individual research," she says. She chose to come to the school after realising "she didn't need exams", she adds.
The Acorn School's curriculum, which was designed by Mr Whiting, aims to educate children to get to know themselves and the world around them.
It draws on some of the principles of Steiner schools, where there is an emphasis on an all-round academic, artistic, physical and moral education.
It began in 1991 at Mr Whiting's home with four children who had been bullied, and the intake gradually increased through word of mouth.
It charges fees but the principal insists they are lower than most private schools.
The school's pupils participate in water sports
Pupils take part in daily arts and crafts ranging from metal and woodwork to jewellery and even canoe-making.
There are regular trips within the UK and Europe for all pupils, to practise sports or learn about ancient civilisations and other religions.
The pupils seem to feel they are privileged and treated as individuals, rather than being labelled or being under pressure to conform.
"We actually like school," 17-year-old Amelia says. "And we feel a certain loyalty.
"Here you can be respected for whatever you are good at. There's no careers check list and we're not being pushed towards a career in year 10."
The subject of the "main" morning lesson, currently politics, changes every few weeks.
Chatting to a class of 17 pupils and their principal, several describe feeling happier and more comfortable than at their previous schools.
"I wasn't being taught in the right way" or "you could get away with not working and still pass" are common sentiments towards the state system. And several refer to the Acorn School as a "family".
The close personal relationships do not cocoon children or replace families, Mr Whiting says, but help them to get to know their own identity so they are prepared for later life.
Pupils are discouraged from indulging in parties, smoking or heavy drinking.
"You don't need drugs and alcohol to complete yourself," says Grace, "which is what some people feel."
Discipline appears not to be an issue even worth discussing.
Question of size
The size of the school is important, Graeme Whiting says, but so are its attitude and values. Places are only allocated after a week-long trial in the school.
"You can't just get a place here because you can pay. This is a moral education. We do have strong principles and we expect pupils and their families to uphold them unequivocally.
"The important thing is to give people a centre, so when they do meet the adult world they are prepared and can make their own choices."
Art is emphasised in the lower school
Some may think the school elitist, but they would be wrong, he adds. It is for those who want an alternative with high standards.
But this is not about just taking well-behaved, middle class children who would thrive anywhere, he says.
Not all pupils come from stable families or wealthy homes. Some are sponsored by Christian charities.
Ofsted has praised its teaching quality, curriculum and extra-curricula activities.
But are there any opportunities such a small school cannot provide?
Be'eri, from Israel, says he may have a greater circle of friends at a larger school - but most feel the absence of cliques is a greater advantage.
Mr Whiting says he wishes that the breadth of opportunity at the Acorn School were available to all, and says education would benefit from a smaller scale.
"Education in this country has been watered down," he says. "There are systems for the masses - whereas everyone here is an individual.
"But I don't believe in private education," he said.
"If I could offer all this for free I would."