The words of Piaget on Children's play

“Jean Piaget theorized that a child’s mental models, or cognitive structures, are based on the child’s activities;  engagement makes meaning.  Free, unstructured play is healthy and, in fact, essential for helping children reach important social, emotional and cognitive developmental milestones.  Piaget’s theory is based on the idea that the developing child builds cognitive structures known as mental maps, or schemas, for understanding and responding to physical experiences.