1. The Formal Operational Stage

2. The formal operational stage (11 years onwards) At this stage, the child’s mental structures are so well developed that ideas and problems can be manipulated mentally without the need for physical objects. Children can think about possible occurrences and imagine themselves in different roles without the need for dolls or play-acting. They can also think about hypothetical problems and abstract concepts they have never encountered before, such as: A > B > C, then A > C (where > means ‘is greater than’) Piaget believed everyone reached this stage by the age of 20.

3. Bradmetz (1999) Badmetz studied the cognitive development of 62 children from the age of 7 until they were 15 years old, regularly giving them a battery of tests, including the Inhelder and Piaget science task, designed to measure formal thinking. Only one of the 62 young people proved capable of formal thinking- less than 2%. Of course, if they were tested again at the age of 20 many more may demonstrate formal operational thinking, but Bradmetz’s results do at least show that formal thinking tends to develop later than Piaget believed.

4. Piaget (1958) Piaget (1958) gave Swiss school children some science questions and gave them the task of devising hypotheses and carrying out experiments to test these. One such task was to investigate the pendulum problem. Children were given pendulums of different weights and string of different lengths. Their task was to determine whether the speed of the pendulum depends on its weight or the length of the string. It was found that most 11 to 15 year olds were capable of setting up and carrying out this and similar tasks.

5. Summary: By the end of this stage, adolescents or adults can use formal, abstract logic. This means they can think about what could happen or what would ever happen. They will also approach problem solving in a systematic way.