Sir, - The recently published report of the Task Force on the Physical Sciences contains the preliminary findings of a study carried out by David Millar and Ruth Murphy of the educational research unit at St Patrick's College, Drumcondra. This compares the grades awarded in different subjects in the Leaving Certificate.
The task force commissioned this study to ascertain whether it was more difficult to achieve high grades in the physical sciences than in other subjects. The Commission on the Points System (1999) expressed concern in its final report about the extent to which students' subject choices were influenced by the perception that some subjects are likely to be marked "more easily" than others.
Millar and Murphy carried out an analysis of subject difficulty using a method called subject pairs analysis. This compares the mean grades of the students sitting a target subject with their performance on a comparison subject. In this way, both chemistry and physics were compared individually with the 16 most popular higher level subjects, using the Leaving Certificate results of 2000 and 2001. In 2000, in chemistry, the mean grade achieved by the group was a C1 while the mean grade of the comparison subjects was B2. The mean grade for physics was also a C1 and the mean grade in the comparison subjects was a B3. So chemistry and physics respectively were apparently marked 1.5 grades and 1.0 grade more severely than the comparison subjects.
In the Leaving Certificate of 2001, the mean grade in chemistry improved to a B3 but was still 1.3 grades lower than the mean grade for the comparison subjects. Physics, in 2001, dropped to a mean grade of C2, and was 1.7 grades lower than the mean grade for the comparison subjects. The authors rank this grade difference in subjects as an estimate of the severity of the subject.
Their work shows that grades in physics and chemistry have consistently been lower on average than those achieved in other subjects. Their work also shows that although the mean grade in chemistry has increased by just over one grade between 1996 and 2001, its estimate of severity has remained high in relation to other subjects.
Overall, the study shows that students sitting higher level chemistry and physics in the Leaving Cert of 2000 and 2001 did consistently less well than in other higher level subjects. This is obviously an issue of great concern to the members of the Irish Science Teachers' Association. The perception that high grades are harder to attain in the physical sciences turns out to have a strong statistical basis. As has already been pointed out, students tend to select subjects for the senior cycle on the basis of how easy it is to achieve high grades in Leaving Cert. This study demonstrates that the dice is loaded against the physical sciences.
The Irish Science Teachers' Association urges the chief examiners of both Physics and Chemistry to consider the findings of this study, particularly in relation to this year's examinations in both subjects. Physics and chemistry of 2002 are the first papers set on the revised syllabi in both subjects. It is no understatement that the future survival of these subjects depends greatly on the perception that a student can expect to perform in the physical sciences on a comparable level with his/her other subjects. - Yours, etc.,
SIOBHÁN GREER, Chair, Irish Science Teachers' Association, Blackrock, Co Louth.