Concrete Operational Stage of Cognitive Development
During the Concrete Operational Stage, children gradually develop the ability to 'conserve', or learn that objects are not always the way that they appear to be. This occurs when children are able to take in many different aspects of an object, simply through looking at it. Once children have learnt to conserve, they learn about 'reversibility'. This means that they learn that if things are changed, they will still be the same as they used to be. For example, they learn that if they spread out the pile of blocks, there are still as many there as before, even though it looks different (Edwards et al., 2000).