It is unfair to think Montessori teachers are debs filling in time before finding a man with money, says Karen Pearce, who with the help of three classroom assistants runs the Hampstead Montessori School or Children’s House. Theirs is a profession not to be taken lightly, she says. “We experience the same stresses as mainstream teachers.”

Montessori salaries are not high - they generally start at Pounds 9,000-Pounds 10,000 with increases according to inflation and responsibility. And the training, which can last up to two years and costs almost Pounds 2,000, is not recognised by the Department for Education and Employment.

On top of that, at the end of the training course the successful students are shadowed by a more experienced teacher for one year before being allowed to take over a class.

Students must be at least 18 years old with minimum qualifications of two A-levels or eight GCSEs (or the equivalent national qualification). But what they must demonstrate above all else is a belief in the Montessori philosophy that “it is a matter of being not a matter of learning”.

“It is about using children’s intellectual response to their environment to try and understand them,” says Karen. “All children want to learn and a teacher’s job is to harness this curiosity and use it to open the children up to learning.”

The Montessori system is named after Doctor Maria Montessori, who was born in Italy in 1870. It revolves around a carefully structured room, known as the Children’s House, with specially designed materials that allow the child to be in control of his or her own learning. Dr Montessori believed that children up to six years could not be directed or corrected using reason and that as far as possible these two elements should be inherent in the structure of a child’s environment as part of a stimulus to acquire new skills.

Pupils start at Montessori schools between the ages of two and three years and stay until five or six. The day is split into morning or afternoon sessions with children arriving at 9 am.

The older ones go straight to their chosen activities - these range from playing to reading on their own, to painting. The younger ones perhaps will go to a “grace and courtesy” group where they learn how to greet people, shake hands and settle in with the others.

Every child is allowed to work on their own for as long as they want without fear of comparison or competition. They are taught to respect others and if they want a particular piece of equipment they have to wait until another has finished with it. But when the activity is completed the child must put the equipment away exactly as it was found. If the equipment is put away badly, the teacher must be on hand to take it out again and demonstrate how to repack it.

“The teacher’s job is to open the children up to learning, but they must also learn the children’s personalities”, says Lynne Lawrence, Director of Training and School in Hampstead.

There is no homework because children work with materials in a very specific way in the classroom that cannot be replicated at home. And each day teachers spend five minutes considering Montessori’s lessons or sharing presentations and ideas.

Teachers are required to spend time just watching the children, giving them long uninterrupted periods to concentrate and develop their own responsibility.

Parents are encouraged to drop in at any time and anyone peering through the one-way observation panels at the Hampstead Montessori Children’s House would see a room of two to six-year-olds wandering from table to table, sometimes delving into boxes and trays, sometimes reaching for the colourful beads that hang from the wall in the maths corner.

It is a tranquil scene and one that can easily make you forget this is a school. The youngsters in the room, with its child-sized furniture and equipment, are absorbing new skills through exploration and observation, seemingly without much effort.

Fees at Montessori schools, which enjoyed a boom in the Eighties, are around Pounds 800 a term.

Disciples will point out children are taught to be self-sufficient, not only in things like tying shoelaces, but also in organising their own work. And a Montessori teacher will never correct a child. If one comes to the conclusion that two and two make five, the teacher will say nothing. Instead she will demonstrate maybe the next day why it’s not right.

“Eventually he will learn for himself that two and two make four,” says Karen Pearce. “The basic equipment has a wonderful logic and children learn reading, spelling and arithmetic at a very early age without realising it and without being pushed.”

The Maria Montessori Training Organisation, 26 Lyndhurst Gardens, London NW3 5NW. Tel: 0171 435 3646.

Monique Vroemen at the Montessori school in Hampstead: the teacher’s job is to open the children up to learning, but they must also learn their personalities.