SuccessfiedJean Piaget held that children construct knowledge by acting on the world, and that their thinking changes in quality, not just in amount, as they grow. He described four stages that every child passes through in the same order, though not at exactly the same age.
- Sensorimotor (birth to about 2 years): the child learns through senses and movement; object permanence develops.
- Preoperational (about 2 to 7 years): language and symbolic (pretend) play grow; thinking is egocentric, centred on one feature, and not yet reversible, so conservation is not understood.
- Concrete operational (about 7 to 11 years): logical thinking about concrete objects — conservation, reversibility, classification and seriation.
- Formal operational (about 11 years onwards): abstract and hypothetical thinking; testing ideas systematically (hypothetico-deductive reasoning).
In class, this means matching tasks to the child's way of thinking: concrete materials and activity for younger children, and reasoning with hypotheses for adolescents.