This period is known as the concrete operational stage, which is the third stage in Piaget's theory of cognitive development. This period spans the time of middle childhood—it begins around age ...

children enter the preoperational stage at around two years old Despite being over 70 years old, Piaget's theory is "still one of the prevailing theories in terms of cognitive development," Dr Sam ...

Piaget found four major developmental stages (with many subdivisions). For the first year and a half or two years of life, infants are only aware of sensorimotor experience, and do not connect it ...

This period, known as the formal operational stage, is the fourth and final stage of Jean Piaget's theory of cognitive development. It begins at approximately age 12 and lasts into adulthood.