In summer 2008 GCSE maths in England will be examined in two tiers rather than three. The decision to adopt this model has been reached without the trialling of its effects on teaching and learning and, indeed, the evaluation showed mixed responses to assessment trials, but the responsibility of the mathematical teaching community is now to make the most constructive use of it for students.

The reaction of many has been very positive, because all students, whatever their tier of entry, will now be able to aspire to the all-important grade C. However, specifications have only recently been approved and posted on websites, and the evidence is that many departments, caught up in the unrelenting pressure of preparing students for key stage 3 exams, GCSEs and ASA-levels, have not yet thought clearly about the implications of these changes for teaching and learning, for schemes of work, grouping and so on, and yet many are in the process of teaching the new specifications.

Who are the students who will gain from these new tiering arrangements? I would suggest potential grade D candidates, who can take a foundation paper - which they can tackle with the confidence of achieving grade D while aspiring to grade C, giving them a good foundation for progression to grade C at a later date. But weaker candidates, who may have no realistic chance of gaining a C, will be faced with papers which are more daunting.

The strategy to be adopted for C-potential students is not clear.

Foundation papers will require mastery of most of the material tested in order to gain a C - which is surely a good thing educationally. But it will then be possible for astute teachers to “cherry pick” higher-tier material in order to build up the relatively small number of marks needed to gain a C (the eventual advent of a functional maths hurdle should help to address the worst abuse of this possibility).

Students with BC potential will be tackling papers which for them are relatively difficult, and the most able will have only a comparatively small part of their papers focused on material that has been new for them in key stage 4, so reliability of outcome must be an issue. These students will now have more marks allocated to work they were introduced to in earlier years, and whereas it is important to demonstrate they have mastered basics, the terminal papers will be an odd test for the most able.

It will be tempting for some teachers to concentrate on consolidation of easier, sometimes relatively unimportant, techniques at the expense of the “stretch and challenge” on which we hope many of these students will want to build.

More concerning still is that coursework, at 20 per cent of GCSE weighting, will have for the most able the same weighting as AA* material (25 per cent of the 80 per cent allocated to written papers), which again reflects the issues of reliability raised in the trial two-tier assessments.

The same comments apply to CD students taking the foundation tier. In terms of resources, most publishers have produced two basic texts, one at each level (though OUP has been more perceptive). Before departments rush into multiple purchases of these, they should look carefully: some are very good - for a small proportion of students. Inevitably, any one book will be pitched correctly for a minority, and many departments would do better to continue using their present texts, supplementing them when they have decided what the best diets are for each of their groups of students.

Here is the real opportunity of this change: there are more than two sorts of students at KS4, so a simple division into foundationhigher won’t work.

Most departments have students from KS3 on, and the more reflective now have a catalyst for reappraisal of their programmes of study from 11 to 16.

What skills and processes make a coherent and challenging progression for your students, to GCSE and beyond? In what setting will the mathematical learning of each individual be optimised and the internalisation of Ma1 integrated? What resources do you need to support that? Which of the GCSE specifications now on offer - linear, modular by topic, or graduated - best supports those decisions? Finally, and it need not be until shortly before exam entry, which tier of entry will enable each student best to demonstrate what they can do confidently and how they can think? Only if we make those decisions in the right order will our students fully benefit from this change.

Jennie Golding is an AST and head of maths at the Woodroffe School, Dorset. She chairs the teaching committee of the Mathematical Association, but writes here in a personal capacity