What are the key skills developed in the concrete operational stage?

The concrete operational stage, which is part of Piaget's theory of cognitive development occurring approximately between the ages of 7 and 11, is characterized by significant advancements in logical reasoning and the understanding of concepts such as conservation and hierarchical classification.

During this stage, children begin to think logically about concrete events. They understand that certain properties of objects, such as volume, mass, and number, remain the same even when their shapes or appearances change—this is known as conservation. For instance, a child can recognize that if water is poured from a short, wide glass into a tall, narrow glass, the amount of water remains the same despite the change in shape.

Moreover, children in the concrete operational stage can classify objects into different categories and understand the relationships between those categories, which is referred to as hierarchical classification. They can group objects based on shared characteristics and recognize how those groups fit into larger hierarchies.

These skills mark a significant advancement from the earlier preoperational stage, where children were limited in their ability to think logically and often relied on egocentric perspectives. Thus, the key skills developed in this stage focus primarily on logical reasoning and an improved understanding of relationships between objects and their characteristics.