The ways boys and girls (N = 119) at different grade levels rated and explained their potential for improvement in mathematics and the mother tongue were compared in order to examine their subject-specific notions of the malleability of their academic ability. The findings indicate that children perceive their potential to improve their performance to be higher in mathematics than in the mother tongue. In the mother tongue the children's ratings of their potential for improvement became more pessimistic with advancement in the child's grade level. In mathematics the boys rated their potential for improvement higher than the girls did and trusted exertion as a means of improving their performance more than did the girls. Those children who gave optimistic ratings of their potential backed up their view by referring to the possibilities of practising and to the positive academic recognition they had received, and the role of these explanations grew stronger with advancement in the child's grade level. In contrast, those children who gave pessimistic ratings of their potential backed them up by referring to their poor performance and deficient ability. It was concluded that the optimistic pupils seem to place themselves in the 'promotional sphere' of the institution of school, whereas the pessimistic pupils seem to place themselves in the 'restrictive sphere' of education.