Research on Piaget's four stages of cognitive development has shown that although nearly everyone passes through sensorimotor, preoperational, and concrete operational stages, most do not reach the stage of formal operations. Those people who do attain formal operations seem to have a curiosity factor not operative in those who don't. (Author/BRR)

Asserting that play encourages development of the cognitive map, this article describes the development of a cognitive map and explores the function of play in that development. (JC)