ABSTRACT
In a period of time marked by Glasersfeld’s presentation of radical constructivism to the Jean Piaget Society in Philadelphia in 1977 (Glasersfeld, 1987/1977) and by the publication of the Curriculum and Evaluation Standards by the National Council of Teachers of Mathematics in 1989, radical constructivism became a major force for reform in the teaching and learning of mathematics and science in the schools (Steffe and Kieren, 1994). The focus of this reform, which continues today, was different from the focus of the reform movement of the ‘golden age of reason’ of the 1960s. In the earlier reform, the old mathematics and science curricula were replaced by modern curricula, and institutes were held to prepare mathematics and science teachers to teach them. In spite of being the proposed view of learning and teaching in the modern mathematics curricula, discovery learning (Hendrix, 1961) and discovery teaching (Davis, 1966) had little impact on the practice of mathematics education. Teachers became experts in the concepts and principles of the subjects they taught, but most of them knew little about the psychological or epistemological foundations of mathematics education. As a consequence, in the main teachers simply taught the modern curricula in the same traditional way they had taught the old.
