This document provides an overview of several theories of teaching and learning mathematics, including Piaget's stages of cognitive development, Bruner's stages of representation, Dienes's theory of mathematics learning, behaviorism, information processing theory, constructivism, Vygotsky's zone of proximal development, Van Hiele's levels of geometric thinking, theories of visualization and representation, Skemp's instrumental and relational understanding, and Gagne's learning hierarchy. The document was presented by Dr. Chew Cheng Meng from the Universiti Sains Malaysia on theories of teaching and learning mathematics.