There are a few wily short cuts that can make a big difference - but the exact approach can only be determined by the person who is going to have to sit the GCSE, A-level or other exam.
The first and most basic point is to make a solid revision plan, says Dr Val Brooks, a specialist in educational assessment from Warwick University's Institute of Education. "Research on undergraduates shows that those who have a working style based on breaking down tasks into small, manageable parts end up with better degrees," she says.
Revision should never simply be seen as soaking up knowledge. Pupils should try to get involved in what they are studying - preferably by trying to marshal the topics they are revising.
Parents should not stop their children from revising with a friend, if they are explaining concepts to one another, she says. This can be one of the best ways to understand a complicated subject. Writing out plans for exam answers and doing timed exam questions are also important.
Anyone who is going to sit an exam needs to have as good a knowledge as possible of the marking scheme, according to Dr Brooks. Teachers should pass on to pupils details of specimen material from exam boards. These model answers help to show exactly what the difference is between an A star and a C grade, and show students just how much work they need to do.
It is generally better to have a series of intensive study periods followed by a short break. The length of time individuals can concentrate for varies, but Dr Brooks believes a 40-minute session followed by a 10-minute break and another session is a good way to start.
Writing down key points can help to build up a sort of index in a student's memory that can unlock more detail once they have written down a few key words.
Dr Rosemary Stevenson, a researcher in learning at Durham University's psychology department, says: "People who say they can't revise are talking themselves out of it. Motivation is at the root of learning. That is why some people find it easier to learn than others, although how we learn is a very complicated subject."
Some students, for example, like to use colour-coded charts, while others favour writing out notes. There is a lot of research on different learning styles, but no clear view about which technique is best. Colour coding, for example, may help students to learn facts, but it won't help their understanding - which is the key to doing well.
Being organised is one of the most important skills any student can have. It is also the best defence against a panic attack during an exam.
If you start to panic, the best thing is to control your breathing by taking slow, deep breaths. After that, you should move on to another question before coming back to the difficult section later.
Students who are extremely anxious about exams should consider professional counselling. But for this to be successful, it is necessary to start during the spring term, because it usually takes several weeks to take effect.
George Turnbull, spokesman for the Associated Examining Board and author of the booklet How to do Better at Exams, advises students to be realistic and to start revising soon. "For most students, the hardest thing is getting started. It's best to do about 10 minutes a night and build up to doing more revision later," he says.
If parents try to intervene too strongly, they may end up turning revision into a battleground. The best way for mothers and fathers to help is by being supportive. During the final few hours before an exam, they should do everything to help students to feel relaxed.
And anyone taking GCSEs or A-levels, remember: history is littered with famous people who did not do well in exams.
First cereal and toast, then the work begins
It is 8am and the rain is lashing the classroom windows. Early- morning revision at Coundon Court School is about to begin.
The room smells strongly of toast. Around 20 16-year-olds are crunching their way through breakfast laid on by the Coventry comprehensive to fortify themselves for maths GCSE revision. Also on the menu is the Fibonacci Sequence and revising square numbers.
The school is unusually silent at this early hour and the pupils uncharacteristically quiet. Downstairs another group is revising science, refreshing their knowledge of photosynthesis.
Maths teacher Simon Ellis is in favour of the 8am slot. It is the best time to teach, he says, though he knows he is teaching the converted: the harder-working students.
Most revision-class pupils are aware that they have reached make-or-break time for their GCSEs and that a grade C in maths is vital. Vicky Vincent- Betts, 16, speaks for many: "The GCSE exams are not far away. They're just nine weeks off and I'm quite worried about them.
"For the first couple of weeks it was quite hard to start school this early, but I've got used to it and I've saved time by cycling instead of walking."
Matthew Jones, 15, doesn't mind getting up at 7am. He knows he needs maths and it seems sensible to come in early one day a week if that made the difference between a C and a D.
Coundon Court runs the classes as part of a series of additional revision sessions that began two years ago. There are also lunchtime, after-school and holiday classes, though the early-morning sessions were only started this school year.
Teachers coming in early are given time off in lieu. The school is a technology college and has been given extra funding which helps to cover the cost of employing more part-time staff.
But the headteacher, David Kershaw, says the revision sessions would have gone ahead anyway because they are crucial to raising standards, particularly in helping students who might have got a grade D to achieve a C.
The school has an impressive record of improving GCSE grades. The percentage of pupils gaining five A-C grades has risen by a fifth over the past four years, to 58 per cent.
A guide to the guides
There is a huge range of guides to help students study for exams - in book form and on the television, and increasingly through multimedia. In addition, students are helping one another. Here are some aids:
n It is possible to buy a guide to revising GCSE physics written by sixth-formers at Manchester Grammar School, based on their own experiences.
n The Associated Examining Board and Barclays Bank have published a free booklet, How to do Better in Exams. To order, phone 0990 102222.
n Longman is one of a number of publishers producing traditional study guides. The guides, written by experienced examineers, cost pounds 9.99 and cover 21 GCSE subjects. Longman produces exam practice papers (pounds 4.99 each) and a CD-Rom covering English, maths and science (pounds 19.99).
n The BBC has produced a GCSE Bitesize package including books, television programmes and an Internet site. The package covers seven subjects, and the books cost pounds 4.99 or pounds 6.99. The TV programmes are designed to be recorded, and access to the Internet site is free.
n Manchester Grammar School's physics revision guide costs pounds 6.95 and is on sale in Waterstone's and Dillons bookshops.
In their own words ...
Gareth Fowler,16, five GCSEs at C and above.
"Extra tuition in maths was critical for me. I got a lot of help on how to answer questions. I found exam technique a bit difficult. I also had help making sure I could understand things like Pythagoras' theorem and trigonometry."
Carl Hudson, 16, five GCSEs at C and above, A-levels in information technology and geography.
"I got extra tuition in maths and it raised my grade from a D to a C. I want to work as a computer technician, and I wouldn't have had any hope of getting a job without it."
Sukhbir Atwal, 17, English, history and media studies at A-level, says having extra help has improved his maths grade. "I was on for a C in maths and I could have just carried on, but I wanted to get a higher grade and going to a revision session helped me."
Marie Hancocks, 16, English, history and geography A-levels: "I went to several revision sessions. They were a confidence- booster and gave me pointers about how to lay out answers."
School: Sharnbrook Upper, Bedfordshire.
Claim to fame: Grant-maintained comprehensive with Ofsted award of excellence.
Passed/failed: 62 per cent of pupils gain five A to C grades at GCSE. Students come from what Ofsted called a ''slightly favoured'' catchment area.
n Pupils advised to take half-hour breaks every two hours and then revise another subject. Staff say research has shown it is difficult to concentrate on revising the same subject for more than a couple of hours.
n Sixth-formers encouraged to talk to GCSE pupils, urging them to study.
n Parents are shown how to help their children revise.
Fred Birkett, deputy headteacher: ''Preparing your revision properly can increase your mark by two grades. March is about as late as you can leave starting to revise''.
The school: Manchester Grammar
Claim to fame: Founded in 1515, it is the largest independent day school in Britain. It has a 100 per cent pass rate for gaining five A to C grades at GCSE.
Passed/failed: School is highly selective and pupils all have IQ scores in the top 6 per cent.
n Pupils urged to get organised in the second half of the spring term.
n Absolutely vital for pupils fully to understand everything they have learnt before they revise. Many pupils miss some lessons through illness or fail to understand all topics.
n Sixth-formers published their own revision guide to GCSE physics this week. Other guides will follow.
Dr Martin Stephen, High Master: ''If you put rubbish in, you get rubbish out."
School: Northicote, Wolverhampton.
Claim to fame: The headteacher, Geoffrey Hampton, was knighted in the New Year honours list for turning around what was a failing inner-city school.
Passed/failed: Results are rising. The percentage gaining five A to C grades at GCSE are up from 10 to 12 per cent. The percentage of children gaining five A to G grades is up to 87 per cent.
n Sixth-formers talk to 15- and 16-year-olds to encourage them to revise.
n A special parents evening is held to offer tips on revision and advice on what standards are expected.
Sir Geoffrey: "All those taking GCSEs are given a revision guide, containing tips on studying and model revision plans. During the week before the GCSE exams begin pupils are shown around the hall to help calm them down."