To attain the aims of mathematics eduction, it is necessary for mathematics to be taught, provided teaching is understood broadly enough to include liberal forms of pedagogy. Thus a theory of the teaching of mathematics, including the role of the teacher, is required. The teaching of mathematics has been transformed during its history, by developments in the area of resources for teaching and learning mathematics. Texts, calculating aids such as electronic calculators, and microcomputers, for example, play a central role in mathematics education. Thus it is appropriate to include a theory of resources for mathematics education as an element. In his general model of an educational ideology, Meighan (1986) includes such a component.