As babies develop into young children they naturally engage in different forms of play. Mildred Parten, a contemporary of Piaget and Vygotsky, described 6 stages all children will go through as they grow and develop. These stages are linked with their cognitive development.
It is useful to understand where children are in their development of play, as even though children may be chronologically old enough to be at stage 6, their past experiences and development may mean they are still at a more developing stage. We need to ensure we are not expecting them to do something they are not cognitively ready to do.
