News that a cleaner had consigned a piece of work by artist Damien Hirst, which included Coke cans and ash trays, to a gallery dustbin, was manna to the British tabloids. As often with Hirst nothing is new; this has happened to other modern artists, but it raises the perennial question “what is art?” which continues to provoke public hue and cry. The related question “what makes an artwork good or bad, strong or weak?” continues to set hares running among the art establishment. Any visit to the Tate Modern or analysis of contemporary art will tell us that there are no certainties.

Yet art teachers in schools are called on to make these judgments all the time - to define, assess, mark and grade art for the purpose of examination. On the whole, unlike the world outside, a degree of consensus, based on experience and connoisseurship, has been reached. Art teachers and the external moderators, who come in to check the ranking order of candidates, have generally reached agreement on whether the body of a student’s work is worthy of a C or a B. In recent years, however, teachers have become increasingly unhappy with what they see as government moves to whip the subject into line, to make it more measurable and therefore more objective.

Where once teachers and examiners could allot a grade to an entire body of work, the sum of two or three years of a pupil’s endeavour, now they must break down each pupil’s art project into fragments for assessment, awarding a series of marks for a series of criteria. Pupils must produce clear evidence that they have met the criteria which cover, for example, the recording of observations; responses to primary sources; the critical and contextual understanding of the work of other artists and cultures. It is the process, say teachers, that has become all-important, and the final and finished object itself has little influence on the exam grade. They criticise the Qualifications and Curriculum Authority, which regulates exams, for making art into a hoop-jumping exercise, and creating a topsy-turvy world whereby a candidate with poor creative and technical ability can nevertheless gain a decent grade if all the boxes can be ticked. Conversely, they say, a candidate with obvious artistic flair can suffer if evidence of process is deemed insufficient.

Criterion-based marking is not new, but the reins appear to be tightening. This summer a spat between art teachers and Edexcel, the exam board that attracts the highest number of GCSE art candidates, threw the spotlight on the entanglement created by this drive for objectivity. Edexcel’s art GCSE has been under the scrutiny of the QCA for several years due to the notably higher percentage of A-C grades, and A*s in particular, awarded to its candidates. Teachers are still smarting at the board’s notification late in the day that it would apply the assessment criteria more strictly in the approaching summer exams. This, combined with decisions on the setting of grade boundaries and a complex number-crunching operation by the board’s computing system, left many departments depleted of A* grades and with A-C percentages down by one third. Edexcel acknowledges that “grades were not so good this year” (art was one of only seven out of 37 GCSEs where A*s decreased) but that “academic rigour” was being emphasised. A spokeswoman says: “There is more rigour in the processes all the way through, more externality.” Teachers accuse Edexcel of a knee-jerk, over-the-top reaction to pressure from the QCA to tighten up on their marking procedures.

Even teachers who approve of developments in the GCSE syllabus are angry at the board’s behaviour. Gail D’Ath Green, head of art at Sacred Heart Girls’ RC High School, Hammersmith, west London, welcomes the academic drift but says her students suffered from Edexcel’s late decision to apply the criteria more rigidly (her department gained no A*s this year). She approves of the requirement for students to keep sketchbooks and show that they have looked at other cultures, periods and artists throughout their work. She says: “We are asking too much of pupils to get them to produce work of quality without referring to art history or the work of other artists. I think it is a mistaken notion that children will come up with wonderful art from their imagination if left to work on their own.”

But while most teachers would support the need for students to look at other cultures and periods in art, they believe the way the criteria is being applied is leading to the fragmentation of art. The sum of its parts, they say, no longer make up the whole. A senior Edexcel examiner has acknowledged that while students should pay “due attention” to historical context and contemporary work, the requirement to meet such criteria in every piece of work “becomes a hurdle to getting a good grade for some students doing exciting work”.

“In the past if you could discern within a piece of work that the student had tipped their hat at the work of, say, Howard Hodgkin, then that would be enough,” said Barry Fincham, head of art at The Priory School, a secondary in Orpington, Kent. “Now it has to be slavishly documented and students who are creative but not necessarily good at recording are being penalised.” Mr Fincham saw his GCSE A-C grades fall to 46 per cent compared with 78 per cent last year, but said A-level was also becoming “heavy on documentation”. He says: “So much stuff has to be recorded in work journals that we are struggling to find an opportunity for studio art work.”

John Steers, general secretary of the National Society for Education in Art and Design (NSEAD), says exam assessment is now driving the art curriculum in secondary schools and the “spurious search for objectivity” is putting an emphasis on activities which are not at the core of art and design. He says: “We have stopped assessing creative and technical skills and the imagination of students.”

John Bowden, an art consultant and vice-president of NSEAD, says the emphasis on planning and the use of sketchbooks, while valuable, does inhibit art which involves using media in a direct way and which does not by its nature involve prior investigation or “gathering of systematic evidence or imagery”. His recent research into boys’ underachievement in art (the gender gap is wider than in any other subject) suggests that boys in particular are resistant to preparatory work in sketchbooks before doing final projects. (A summary of this research has appeared in AND, the art education magazine of NSEAD. For a copy tel: 01249 714825.) Martin Walker, head of art at Barlby High School, Selby, Yorkshire, who helped in the research, has found that some of the difficulties boys experience in having to plan and investigate in sketchbooks is offset if they are involved in making three-dimensional work. He says: “Boys like to build something, to be making. All our top grades this year went to boys.”

Elizabeth Nuttall, head of art at Tomlinscote School, a secondary near Guildford, Surrey, saw her A-C grades fall by 37 per cent this year from 100 to 63 per cent. She finds that girls tend to be better at working in sketchbooks and journals and are therefore scoring higher in an exam which emphasises the process of art. She says: “Boys like to know where they are going and to get on with it. The student who is average but meets all the criteria can end up with a good mark. It is very hard to give marks for a superb end product.

“Real artists don’t meet all the criteria in every piece of work they do. By being so prescriptive we are in danger of losing sight of what art is about, which is creativity.”

There is a fear among teachers that art in schools will become increasingly formulaic in order to attain necessary grades and that what is being tested is the strategy of the teacher to cover assessment objectives rather than the creativity of pupils. “Teachers will crack the code,” says Len Green, head of art at Arnwood School, New Milton, near Bournemouth. “It will become painting by numbers.”

EFFECTIVE USE OF SKETCHBOOKS

* Students should regard the sketchbook as a diary or visual journal, which includes their thoughts and experiences and whatever rouses their interest visually or emotionally - this diary should be personal and unique.

* The sketchbook should be on hand at all times, not just as a homework book.

* Students should explore a variety of visual ideas. They should be encouraged to make visual notes with brief written comments. There should also be evidence of more considered recording and evaluation.

* Students can use physical evidence collected from the environment, photographs and other visual imagery.

* Students should be inventive and experimental in their use of media to record ideas. They should develop and extend their art vocabulary.

* The sketchbook is to be used as part of the creative process, but it may also be considered as an end in itself.

* The sketchbook can be constructed by students from a range of innovative media, including the outcomes of previous activity - it could be material collected in a box; or material presented on a videotape or CD. Encourage risk-taking and innovation both in format and content.

* Ordered presentation is not an immediate priority, nor is there a need always to produce careful and complete drawing.