MARKING the exam scripts begins as soon as the first scripts arrive in the exams branch of the Department of Education in Athlone, Co Westmeath.

Indeed, long before Leaving Cert candidates have finished all their exams, the correctors will be marking today's papers.

When students hand up theirs scripts at the end of each exam, the supervisor puts them in an envelope, then seals that and delivers it personally to the post office, from which it makes its way to the exams branch in Athlone,

Each subject has a chief examiner, normally a senior inspector in the Department of Education. He or she is assisted by a chief advising examiner, who is usually a teacher with many years' experience of examining. In large subjects such as English or Irish there is also a team of assistant advising examiners.

Several hundred correctors are recruited for each subject. Again, these are mainly teachers who, in many cases, have been correcting for years.

There are 3,700 correctors recruited for the Leaving and Junior Cert. They apply to the Department of Education for the job and are paid per script corrected. Rates of pay vary depending on the difficulty of the subject, ranging from £8 per script for higher level Leaving Cert English and Irish, down to around £2 at Junior Cert ordinary level.

The first step in the correcting process is a day long marking conference. The chief examiner and the advising examiners produce a "marking scheme" for this conference this outlines points, facts and issues which students might be expected to raise in each answer and allocates marks to these. In drawing up the marking scheme, any misprints in papers or questions that have caused particular difficulty will be taken into account.

Both secondary teachers' unions the TUI and the ASTI and the relevant subject association (the Association of English Teachers, for example) make a report on each exam paper to the chief examiner, and any issues or difficulties raised by them would also be taken into account in drawing up the marking scheme.

If those bodies strongly claimed that question 5 on a particular paper simply was not comprehensible to students, for example, then this would be taken into account.

All the correctors are summoned to the day long marking conference in Athlone. At it photocopies of a number of exam scripts taken from the piles at random are handed out and the marking scheme is tried out on them. Adjustments and changes to the scheme may then be made in the course of the day, depending on how these trials work out. If it is found that there is a lot of difficulty with part of a particular question, for example, the marks for it may be adjusted.

The marking scheme is explained to the correctors and they practise correcting a number of papers. They ask questions and clarify any problems they may have in relation to the marking scheme. Their suggestions may also result in amendments to the scheme. Effectively, it is a training day for the correctors.

They then go home with their bag of scripts and select 20 at random, mark them and return them to their advising examiner who again checks their marking standard. The 10 or so advising examiners each has a group of correctors assigned to them. As the corrector marks away at home, she or he must send in samples of work and marks to the supervising examiner, who ensures that they are all mark ing to the same standard and to check for any unusual blips in the statistical graph

The supervising examiners in turn keep the chief examiner informed and he keeps an overall view of the subject standards nationally. If a corrector seems to be veering outside the normal standards, she will get a visit or phone call from the supervising examiner to bring her back into line.

It is not true that "target" pass, fail or honours rates are set. The examiners are no told "You must only give 2 per cent As in Irish," or whatever, and percentage pass and honours rates do vary from year to year. On the other hand, examiners do keep within the broad parameters of what has been happening in previous years and one is very unlikely to see a doubling of the percentage of As in any subject from one year to the next.

Examiners are cautious folk and where grades do go up it tends to be a slow, gradual process rather than a big jump in any one year.

The correctors do not know whose papers they are correcting only exam numbers appear on the scripts. Neither do they know the sex of a candidate, and the exams branch makes sure that correctors are not given exam scripts from their own school.

When the correctors have finished all their scripts, they return them to Athlone, where the supervising examiners again do random checks to ensure that the standard of marking is consistent. All these checks and balances are built into the system to ensure that all examiners are marking to the same standard and to avoid individual examiners marking according to their personal preferences.