This document discusses several learning theories that can be applied to teaching secondary mathematics, including Piaget's stages of cognitive development and theories of assimilation and accommodation. It outlines Piaget's four stages of development and recommends teaching strategies appropriate for students in the formal operations stage of adolescence, such as exploring hypothetical concepts, justifying solutions, and relating concepts to students' lives. The document also briefly mentions Polya's view of education as developing intelligence and problem-solving skills.