Any school that wants to change its daily timetable may do so: responsibility lies in the hands of the governing body, which must consult parents first. So far, several schools around the country have changed to a continental or 'compressed' day, starting and finishing earlier than usual.
The main advantage is that children do their hard studying in the morning, when concentration is thought to be at its best; the long lunch break is shortened so that lessons do not drag on too far into the afternoon, when pupils begin to tire. Instead, children have more time for educationally valuable after- school activities.
Opposition comes mainly from working parents who cannot collect their children from school before 3.30pm and fear that they will become 'latchkey kids'. Some schools are unable to offer afternoon activities every day, and since participation is optional anyway, children can simply leave and wander the streets if they wish.
Hammersmith and Fulham council says that if enough schools are interested in adopting an earlier timetable, it will guarantee the provision of extra resources for after-school activities. Christine Whatford, its director of education, says the authority is worried about under-achievement in the inner city; she believes the compressed day could be part of the answer.
'We could provide, at the end of the day, subjects that have been squeezed out by the national curriculum such as art, drama, music and dance: the kind of subjects that children, who get switched off at school, become quite motivated about,' she says. 'There would be supervised study areas for children who find the physical conditions at home difficult, extra provision for special needs and opportunities for doing a lot of sports. More able children could study a third language.'
The introduction of a four-term year is something on which the council would have to legislate; its schools would then have to fall in line whether they liked it or not. But judging by the experience of other authorities that have considered such a change, it is unlikely to happen.
When Staffordshire County Council considered changing its school year in 1990, it found that 68 per cent of governing bodies and 'a substantial majority of parents' were in favour of having four terms of equal length.
Those in favour liked the idea of a 'less arduous' autumn term and a shorter summer holiday, which would be easier for parents and mean children lost less ground. They also thought it would be easier to plan the curriculum. Objections, mainly from staff, included a fear of 'innovation overload' and the need for a long summer break to allow teachers to recuperate.
Despite a generally favourable response, the report concluded that the county could not go it alone. Martin Watkins, its spokesman, says: 'It's something that needs to be done nationally. We could not do it in isolation because families with one child in Staffordshire and another in a neighbouring authority would find it impossible.' Hammersmith and Fulham council is likely to run up against the same problem.
Peter Mortimer, deputy director of the Institute of Education, says it is 'very difficult' to change term patterns on a council-by-council basis. 'There are already curious local holiday patterns around the country, such as the wakes weeks in Leicestershire.' National examination dates would also have to be taken into account.
He is in favour of change, however. 'The current situation made sense at one time when a lot of children were needed for the harvest, but now it is unsatisfactory. During the long summer holiday, particularly in the inner cities, children can get into trouble, lose interest in their studies and provide childcare problems for their parents.'
He would prefer a five-term year. 'I have not seen a four-term plan that works. Five lots of eight weeks would create a much more even use of time, still leave a month in the summer and avoid the exhaustion at the end of a long term.'
Anne Rumney, who became head of the Brit Performing Arts and Technology School in Croydon, south London, when it opened in 1991, decided to operate a five-term year and has found that it works well. 'It's easier to plan an eight-week stretch,' she says. 'Parents like it because it breaks down the long summer holiday, and they can go on holiday at cheaper times. The only complaints have come from the few who have children in other schools and find it difficult to arrange family holidays. But several heads have told me that they wished they had the freedom to change to this pattern.'
Those heads are likely to remain frustrated for the foreseeable future. According to a spokesman for the Association of County Councils, changing the school year is 'an issue that is going nowhere fast', because 'it has to be done on a national basis'.
The Government is unlikely to legislate on such a matter. A spokeswoman for the Department for Education says: 'We do not dictate how local education authorities organise the school term, and there are no plans whatsoever to get into a situation where we lay down how the school year is structured.'
Hammersmith and Fulham council is still willing to consider going it alone if consultations show that schools are in favour. Ms Whatford says: 'It would not be easy. We would be out of 'sync' with surrounding areas, and will have to see how big an issue that is.'
Other London boroughs will be watching to see what happens. Chris Adamson, chairman of Islington's education committee, thinks Hammersmith and Fulham is 'very brave' to consider such changes.
'If support among parents for the compressed day is good, we would certainly be interested, although you have to have the extra money to put into it. As for the idea of a four-term year, I think they may face some technical difficulties, but I would not want to pour cold water on it.'