Jean Piaget and his theory
Jean Piaget was a Swiss developmental psychologist and philosopher known his developmental Theory. In this theory Piaget contended that children go through stages to reach full abilities of thinking and understanding the world. His stage theory describes this cognitive development of children. According to Piaget, cognitive development involves changes in cognitive process and abilities. In Piaget’s view children in the beginning make use of actions to understand the world, but later they progress into changes in mental operations.
The following video describes Piaget developmental theory: