Back in 1992 the former education secretary Kenneth Baker wrote in The Times: “I have no doubt that a longer school day produces better-educated children. ” The stumbling block to bringing in so desirable a reform was, of course, lazy teachers and their destructive unions.

John Patten thought the same and told the Office for Standards in Education to go away and research it. But OFSTED inconveniently returned with the view that it didn’t make a lot of difference, and today the Department for Education and Employment says, firmly, that it has no opinion on the matter.

Are longer school days the way of the future, or simply a dying example of the frantic work ethic of the Eighties, when young high-flyers used to say “lunch is for wimps” and walk six flights of stairs to their offices because you cannot use mobile phones in lifts?

What Mr Baker did manage to do in the 1988 Reform Act was to allow governors to decide when the school day starts and finishes. But they cannot make teachers work more than 1,265 contact hours over a 195-day year without agreement with union representatives.

John Patten found that nearly half of all primary schools were ignoring government guidelines which recommended that pupils aged 7 to 11 should be taught for between 21 and 23.5 hours a week. But he also found that more than 80 per cent of primary and secondary schools had increased the length of the taught week since 1989.

Some schools have opted for what is called a continental day. But this is a little like a continental breakfast: it means different things in different countries, and often within countries as well. What the British tend to mean by it is a day that starts early, often about 8.30am, has a short lunch break, and finishes as early as 2 or 2.30pm. A continental day is often confused with a day which has more teaching hours in it, but it may in fact have fewer than the day it replaces.

The main advantage claimed for the continental day is that pupils are thought to learn better early in the day. It also gets rid of the often unsupervised time during a long lunch break, when bullying occurs and the seeds of afternoon indiscipline are often sown.

Tideway comprehensive school in Newhaven, Sussex, operates a continental-day system, and has done since the early Eighties. It opens at 8am with just one 15-minute break in the morning.

Lunch is gulped down between 12.15 and 12.50 - an arrangement made possible by a cafeteria system which gets each child in and out in 10 minutes. The day finishes at 2.15pm and contact time is 24 hours and 50 minutes a week. The school is open from 7am but only the sixth form can get breakfast.

Headteacher Ken Saxby thinks the early start helps children to learn. Reducing the lunch hour, he says, solves the supervision problem and prevents misbehaviour off the premises such as shoplifting and vandalism.

The system also means that no one is forced into the playground. Free time can be spent in common rooms or the library instead. Mr Saxby would like to get rid of the lunch hour altogether, have just one break, and finish even earlier.

By 1991 the continental day was well established in several secondaries, and schools were starting to use the time differently. A growing number had different lengths of day for different pupils. But some educational psychologists were by now challenging the view that children learn best early in the day, and suggesting that crime rates would rise if schools closed in the early afternoon. It was also under fire from parents, with the National Confederation of Parent-Teacher Associations pointing out that a continental day was generally not an option for working mothers.

Primary schools were changing less, though some were compressing lunch hours and starting earlier. Hawkesbury primary school in Avon was, and still is, one of the most radical. Its day starts at 8.30am and finishes at 2pm.

Hawkesbury is a village school with just 120 pupils, and the hours were originally designed to match those of the school it feeds. Working parents benefit from an after-school club which looks after children until 6pm for Pounds 5 a day.

Headteacher Fen Marshall, who inherited the system, says it works well, at any rate in his informal village situation. He likes the fact that it enables the once-a-week swimming lessons to last from 1.30 to 4.00pm, giving children more time in the water.

The 1990s have seen a slow but steady trend towards a staggered and timetabled lunch break. The idea is to feed one set of pupils while you are teaching another set, and then swap them round.

The trouble started when school managements started to add hours to the day. Unions pointed out that if their members’ hours were being changed, they expected a voice, and perhaps a veto. Teachers were already overloaded, and by the time the 1990s came along, increasing the staff was not an option.

But city technology colleges were new, and rich. They were also exempted from the 1,265 maximum contact hours, and their teachers have individual contracts. They adopted the continental early start, but not the early finish.

Kingshurst CTC in Solihull starts at 8.20am. Wandsworth’s ADT CTC has perhaps the longest working day in the country, from 8.30am to 5pm. Leigh CTC in Dartford, Kent, is more typical, with an 8.30am start and a 4pm finish, plus an optional hour’s lesson starting at 4pm. The day is divided into six 55-minute periods. Pupils are taught for 27 hours a week, and get as much homework as if they were in a school with ordinary hours.

Teachers have a minimum of 1,785 contact hours a year and must work 8. 5 hours a day, 42 weeks a year. They are paid on average Pounds 1,250 above the national scale.

As in most CTCs, the long day was partly for public relations reasons. Leigh CTC was founded on the site of an existing school with a poor reputation, and felt the need to show people that it meant business.

Does it work? Principal Virginia Waterhouse says it gives the school “time to do what we want to do. We can give the children greater curriculum coverage and create choice and diversity.” Without the extra time the curriculum would lose its “enrichment” - optional lessons in arts, sport and IT.

Schools are certain to continue experimenting with day length, but the determination to push more into children and squeeze more out of teachers seems to be on the wane. Hammersmith and Fulham in west London, for example, has abandoned plans to become the first education authority to switch all its 47 schools to a continental day from 8.10am to 2.15pm.

The new school day at:Pope John Paul II School, Salford.

8.45-8.55 Registration, prayers 8.55-9.45 Lesson 9.45-10.05 Break 10.05-11. 55; Lessons10.55-11.45 11.45-12.30 Lunch (upper school) and lesson (lower school) 12.30-1.15 Lunch (lower school) and lesson (upper school) 1.15-2.05 Lesson 2.05-2.55 Lesson 2.55-3.05 Registration, prayers Hawkesbury primary school, Avon 8.30-10.15 Lesson 10.15-10.30 Break 10.30-12.00 Lesson (infants) 10.30-12.15 Lesson (juniors) 12.00-1.00 Lunch (infants) 12.15-1.00 Lunch (juniors) 1.00-2.00 Lesson Leigh CTC, Dartford, Kent 8.00 Breakfast 8.30-8. 50 Registration and assembly 8.50-9.50; Lessons9.50-10.45 10.45-11.10 Break 11.10-12.10 Lesson 1.05-2.05 Lunch (including registration) 2.05-3.05; Lessons3.05-4.00 4.00 Optional lesson