The official school mathematics curriculum - textbooks, teacher's handbooks, and syllabus - has a powerful influence on classroom practice in a developing country like Ghana, where many teachers with low teaching qualifications hardly ever have access to other sources of information and activity for their teaching. The official mathematics curriculum for Ghanaian primary schools was originally written with the small intellectual elite, who will proceed to secondary and further education, in mind. Concerns have been raised internationally for countries still using such curricula to adjust them, but the Ghanaian official school mathematics curriculum has remained in use in the nation's schools since their introduction in 1975 with no significant revision. The study, on the one hand, involved an investigation of the extent to which primary teachers in Ghana translate the contents of the official mathematics curriculum into classroom reality. On the other hand, it addressed issues related to the nature, and appropriateness, of the current official primary mathematics curriculum, which was an adaptation of the products of the `new-math' project spearheaded by the West African Regional Mathematics Programme in the 1970s. The study used a range of methods for data collection. These include an extensive content and curriculum analysis of the official primary mathematics curriculum materials, and a questionnaire survey of teachers' coverage of the content and teaching methods prescribed by the official curriculum. The questionnaire survey of teachers' coverage of teaching methods involved the observation of teachers in classroom settings. Tape recordings of lessons and instructions from teacher's handbooks were transcribed to provide both qualitative and quantitative data on classroom practice. The analysis of the curriculum revealed several inefficiencies in the Ghanaian primary mathematics curriculum. Though there was rhetoric in the introduction of the curriculum materials on the use of teaching skills that suggest discovery methods, the analysis indicated that learning/teaching activities that would encourage the use of such teaching skills in the materials were not included. It emerged from the findings that neither what the teachers really taught, nor what the official mathematics curriculum prescribed, was found to be adequate enough to meet the full mathematical needs of pupils. It was found that a very substantial part of the content of the curriculum was taught by the teachers, and both the official curriculum and the teachers, who implement it, emphasised expository teaching methods. It was argued in this light that the low pupils' attainment observed in the subject could not be seen simply as a reflection of the teachers' poor coverage of the curriculum, but as a reflection of inefficiencies within it. The findings of this study corroborate what is known about curriculum adaptation in school mathematics. It showed that coverage of textbooks does influence the emphasis on topics presented by teachers in their instruction, and also that topics in arithmetic are the most emphasised by both official mathematics curriculum materials and in teachers' actual classroom practice.