Cognitive Development Theory

Piaget

Cognitive theory

Explains how children actively construct knowledge as they grow, moving through specific stages of mental development that change how they think, reason, and understand the world.

Sensorimotor Stage (0–2 years)

Learning through senses and movement; develops object permanence.

Ex: A baby shakes a rattle and learns it makes noise.

Preoperational Stage (2–7 years)

Begins using language and symbols, but thinking is egocentric and lacks logical reasoning.

Ex: A child thinks the moon follows them; struggles with conservation tasks.

Concrete Operational Stage (7–11 years)

Thinks logically about concrete events; understands conservation and reversibility.

Ex:A child knows that water poured into a different-shaped glass is still the same amount.

Formal Operational Stage (12+ years)

Abstract thinking; uses systematic problem-solving.

Ex:A teen can understand algebra and debate moral dilemmas.

Core Idea

Cognitive development occurs in stages and depends on active learning, where children build knowledge through interaction with their environment.