This study describes the Nuffield Mathematics Teaching Project with respect to its current use in eleven British schools and eight of the Project's teachers' centres. Data were collected by interviews with Nuffield Project staff members, personal observations of schools and centres, examination of materials published by the Project, and a review of literature pertaining to the Project. It was found that the Nuffield Mathematics Teaching Project attempted to effect change in mathematics content and instructional strategies for children aged five to thirteen. Emphasis was placed on a concrete approach to mathematics, discovery learning and the need to relate mathematics to real life experiences of children. Materials produced by the Project were teachers' guides written by primary teachers, college teachers and Project team members. The study concluded that the Project had a noticeable impact on the mathematics curriculum in British primary schools. One of the major forces in shaping the success of mathematics education in primary schools is the teachers' centres. They have contributed both in curriculum development and in-service education for teachers. The role of the teacher centre has now enlarged to include all curriculum areas and serves many purposes determined by local school personnel. (Author/JP)