The Children (Performances) Regulations of 1968 stipulate that a minimum of three hours’ private tuition must be provided on each day that a child actor would be required to attend school. Thus the BBC’s tutors - freelance but under contract to the corporation - teach up to GCSE level. There is no similar obligation to provide A-level instruction.

Elstree, home to long-running programmes like Grange Hill, has four, small dedicated classrooms. With pupils’ drawings and work pinned on the walls, they could be typical of any secondary school. And there is the library, or “room with books” as Ian Hoskins, head tutor to the Grange Hill cast, prefers to call it.

BBC studios elsewhere are more likely to use a suitable empty room for teaching. When filming on location a “room with books” would be an unlikely luxury, so most tutors make sure they have their own mini-library of thesaurus, dictionary and encyclopedia.

According to Di-May Jones, it’s a question of “have child, will create class-

room”. Tennis clubs, houses and Scout huts have all been pressed into service in the past. Coaches, particularly those fitted with tables, are especially favoured. Open-air classrooms are not unheard

of in summer; when filming Voyage of the Dawn Treader, classes were held on the top deck of a ship.

Classes may be as small as one pupil or as large as 12 - the maximum the regulations permit a tutor to teach at any one time. Work is set by the child’s own teachers and he or she is expected to bring his or her own textbooks. If the work should run out, the tutor will liaise with the child’s school to ensure that more is forthcoming - by fax if necessary.

While they invariably go through completed work, tutors leave the final marking to the child’s teachers. This maintains a degree of consistency, important for GCSE coursework. Public exams must be taken back at school, though this does not extend to a school’s internal exams.

Since just one tutor is responsible for all of a pupil’s subjects, the teacher has to become a Jack or Jill-of-all-trades. “It’s overseeing in a sense, but if a child does not have a clue what to do, then you have to teach,” says Ian Hoskins.

Inevitably some things have to go by the board - like science practicals. But there are compensations: even in the larger classes, the amount of one-to-one tutoring is far greater than most schools can offer.

The four children in the class at Elstree were unstinting in their praise - although they felt the provision of a computer would be helpful.

“It’s a lot easier to get on with your work here,” said one. “The tutors are very good.” Another 13-year-old triumphantly explained how his spelling had improved because of the individual attention he received; another that she was now ahead of her classmates in history.

Nor do production teams have a “hands-off” approach. Di-May Jones recounts the time she was working on the children’s serial Mud, and one boy in particular was struggling with his history work. At the time she happened to be reading an Antonia Fraser novel pertinent to the period - so she loaned it to him. On another occasion, a producer helped coach a child in Latin.

Teamwork is the key: tutor, schoolteacher and child. And it seems to work.One young actress who, having appeared in a programme for several years, returned to school to study for A-levels and was subsequently offered a place at Oxford.

Di-May Jones sums up the philosophy: “No actor can ignore education. We try and drum that into them. If they are going to be actors, they have to learn all their lives.”