The document discusses constructivism and key theorists in constructivism such as Piaget, Bruner, Vygotsky, and Dewey. It outlines their beliefs and theories, including Piaget's stages of cognitive development, Bruner's emphasis on active and discovery learning, Vygotsky's social cognition theory involving the zone of proximal development, and Dewey's advocacy for child-centered learning. The implications for the classroom are that students learn by doing and constructing their own understanding while teachers provide rich learning environments and guidance to support discovery and scaffolding.