Putting Piaget to the test

The over-optimistic predictions Piaget made about the cognitive development of children completing before sixteen were put to the test by Philip Adey, Michael Shayer and Caroline Yates. They developed Scientific Reasoning Tasks (SRT) that could be carried out with whole classes of children. They were based on Piaget and his clinical interviews. Also they developed a Curriculum Analysis Taxonomy (CAT). to measure the cognitive demand of the key ideas of the science curriculum.

This graph summarises the results of 11 000 UK students.

Piaget describes formal operational thinking 3A-3B in terms of the use of variables, classification, proportionality, probability, correlation, combinations, formal models, compound variables and equilibrium

What do you notice about the results and what they say about the formal (abstract) demands of the curriculum from age 14 years of age?