Piaget's Stages of Cognitive Development: Jean Piaget's theory that describes four distinct stages of cognitive development that children go through as they interact with their environment.
Vygotsky's Sociocultural Theory: Lev Vygotsky's theory that emphasizes the role of social interaction and cultural tools in shaping a child's cognitive development.
Zone of Proximal Development (ZPD): The range between what a child can accomplish independently and what they can achieve with guidance or assistance from others.