Developmental Approach

The developmental approach seeks to identify the cognitive skills of adolescence
and to contrast them with the skills found at other ages. This approach
addresses both the qualities of thought and the process of change.
In 1958 Piaget and his coworker Barbel Inhelder published The Growth of
Logical Thinking from Childhood Through Adolescence, a detailed account of
Piaget’s four stages of cognitive development. In addition to proposing that
specific cognitive skills emerge in each stage, he proposes that the move
from one stage to the next is largely maturational.


This statement may be confusing. Clearly, sixteen-year-olds must “know
more” than eight-year-olds, and adolescents have the capacity to learn
school subjects beyond the grasp of elementary school children. The
psychometric approach, however, is not designed to contrast the nature of
cognitive skills at different ages. Intelligence tests are scored by comparing a
specific person to other people of the same age. A score of 100 at age eight
means that a person performs similarly to the average eight-year-old; a score
of 100 at age eighteen means that a person performs similarly to the average
eighteen-year-old. IQ score is expected to remain the same if the person matures
at a relatively normal rate.

Two of Piaget’s stages are of particular importance to the study of adolescence:
the concrete operational stage (ages seven to twelve) and the formal
operational stage (ages twelve and up). During the concrete operational
stage, children acquire basic logical concepts such as equivalence, seriation,
and part-whole relations. Children also master reversibility, a skill allowing
them mentally to restore a changed object or situation to its original state.
With reversibility, children can recognize that a small glass of juice poured
into a taller and thinner glass may look like more juice but is actually the
same amount. During concrete operations, children can think logically as
long as their reasoning is in reference to tangible objects.

The formal operational stage follows the concrete operational stage and
is the final stage of cognition, according to Piaget. Beginning at adolescence,
thinking becomes more logical, more abstract, more hypothetical, and more systematic. Unlike their concrete operational counterparts, formal
thinkers can study ideologies, generate a variety of possible outcomes to
an action, and systematically evaluate alternative approaches to a problem.
Formal thinkers also are better able to adopt a new course of action when a
particular strategy proves unsuccessful. In the Piagetian model, adolescents
are compared to scientists as they utilize hypothetical-deductive reasoning
to solve problems. Although children during the concrete operational stage
would solve problems by trial and error, adolescents could be expected to
develop hypotheses and then systematically conclude which path is best to
follow in order to solve the problem.