Piaget was the first psychologist to make a systematic study of cognitive development. Piaget was interested in how intelligence itself changes as children grow which he called genetic epistemology. Genetic epistemology was based on the 19th century biological concept of recapitulation (Piaget was a biologist first whom later trained as a psychologist).

It was thought before piaget’s studies that children were merely less competent thinkers than adults. However, through his findings, Piaget showed that children think completely different than adults.According to Piaget, children are born with a very basic mental structure (genetically inherited and evolved) on which all subsequent learning and knowledge is based. Piaget based his theory on two major aspects; stages in cognitive development and mechanisms of cognitive development.

Piaget believed that intellectual development only happens when a child interacts of innate capacities with environmental and progresses through series of hierarchical qualitatively different stages. As a child grows his understanding of the world becomes more complex.This frame work is one that all children will pass through in the same sequence. Piaget theory is one that puts the child charge of their learning, he or she is an active participant of their learning rather than a passive receipt of biological or environment input. Therefore they learn from their own experiences. Schemas are the way in which the mind mentally structures and organise past experiences (specific mental or physical action) to provide understanding of future experiences.

It is the building block of intelligence. He believed that children are born with a few schemas.These are adapted and further developed through assimilation. By altering the child’s schema the child incorporates new information into a situation from what they already know (a child given a sippy/drinks cup will use their experience from suckling a breast or milk bottle in order to conquer a new object that is similar).

They have incorporated new information into a new schema. If a schema does not fit through assimilation then the child is forced to develop a new schema, this is called accommodation. Equilibration is the force which drives the learning process; this is the force, which moves development along.Piaget’s four stages of cognitive development are set as approximates.

They are a way of summarising various schemas in a child life at a specific time. The stages are approximates as children transition through them at different rates in contrast to their environment and biological maturation, the child is also able to think in a mixture of two stages. The stages are arranged in ways that the child is continually developing meaning that the stages can be built on earlier ones. Each stage of Piaget’s cognitive development is passed through by the use of cognitive disequilibrium.

Children are forced into thinking and becoming higher level thinkers, new information is to be processed and restore equilibrium, thus making a new schema. A child’s Individual development cannot be understood without references to the social and cultural content as well as language as influences on a Childs understanding. He too suggests that children are active in their own learning.He believed strongly that community plays a central role in the process of "making meaning. " Language being the most important tool within Vygotsky’s theory is used to teach the child form social knowledge.

It can be done by parents, adults, teachers, coaches, experts/professionals – but also things you might not first expect, such as children, friends and computers. These facilitators are called MKO (more knowledgeable others) they are imparting their intelligence as the child learns through instruction; they are helping the child to learn something new that may be too difficult to do alone.Vygotsky’s theory outlines that a child’s use of internalising language is crucial to their development. Through the use of socialising, children are encouraged to talk to themselves, write/ draw how they feel as a tool to their inner monologue. The use of language controls our thinking as well as communicating our thoughts to others; therefore the child is learning to think logically.

“Thoughts becomes verbal and speech rational” ( Vygotsky, 1962). Vysgotsky observed that children are able to complete more difficult tasks if they have guidance. He describes this as scaffolding. Supporting the child is known by Vygotsky theory is ZPD (zone f proximal development). Here is where adult or ‘expert’ guide the child to their full potential. The expert will supply their knowledge of the situation slowly taking away their support or help until the child is able perform the task alone.

Thus, with the appropriate semiotic mediation (scaffolding) the child abilities become sophisticated higher cognitive process. Piaget and Vygotsky are both significant contributors to the understanding of cognitive development. Both theories had the same approach to learning of constructivist; students learn by fitting new information with what they already know.Another similarity of the two theories is that they both believe boundaries of cognitive growth are established by social influences. They both have adapted to a child centred approach to cognitive development with a hands on play orientated theory. Differences include the rigidness of the stages; development is unlikely to proceed in an all or nothing fashion that Piaget’s influences in his theory, Vygotsky however talks about the readiness and ability of the child by having scaffolding by an expert allowing the child to develop their potential with the use of ZPD.

Despite numerous criticisms, Piaget’s theory of cognitive development still remains one of the most influential studies to date, being a foundation of cognitive development. It has prompted further research by physiologists who wish to obtain a further understanding of cognitive development and programs in the belief that children should be taught at a level that they are developmentally prepared in stages. His theory has had an enormous influence in education making education more effective and enjoyable.They have been weaknesses discovered throughout his theory that other psychologists have drawn upon such as Bruner and Bower and Wilshart. Bower questions the ‘sensory motor stage’ of Piaget theory. He talks about the ‘passive exploration’ in his 1981 study of object permanence, he failed to control for alternative explanation in the case of covering up an object from a baby younger than 9 months.

The infant may know that the object is still there but not know how to uncover it.Subsequent researches found ways to test this thesis for example by measuring surprise (Bower 1971). Piaget theory can also be seen as flawed as he seemed to underestimate the abilities of children because his tests were sometimes confusing or difficult to understand (Martin Hughes, 1975). Rose and Blank (1974) questioned whether the child was confused by the questions being asked in the concrete operation stage.

Furthermore, Piaget carried out his studies with a handful of participants – in the early studies he generally used his own children (small / biased sample).Because Piaget concentrated on the universal stages of cognitive development and biological maturation, he failed to consider the effect that the social setting and culture may have on cognitive development. Other weaknesses in Piaget’s theory are that he fails to take in to consideration of children with special needs and how this will affect their development and movement through the stage of cognitive development. in addition to this, there are studies that suggest that Piaget overestimated the ability to use abstractor logic in the formal operational stage.

Dasen (1994) claims that only one third of adults ever reach this stage.Vygotsky was a teacher, psychologist and a lawyer. He was able to apply his practical applications to his studies of cognitive development. Vygotskys theory was broadly generalised, Vygotsky's theory does not provide the richness that Piaget's approach offers, and he did not provide the kinds of specific tools for research that Piaget's many tests and experiments have given us. Vygotsky's approach offers only a general outline of cognitive development; in its emphasis on the social and cultural aspects of learning and cognition, however, it challenges future researchers to explore the role of context in greater depth.

t was not rigid as that of Piaget. It is not tied to specific age group/groups. Vygotsky’s theory pays considerable attention to the socio-cultural, language and social context; this is something that Piaget theory overlooks. According to Berk (2006) in granting social experience a fundamental role in cognitive development, Vygotsky’s theory helps us understand the wide cultural variation in cognitive skills. Vygotsky conducted very few experiments to support his thesis. This can be seen as a less credible theory then that of Piaget.

There has been very little empirical investigating research relating to Vygotsky’s theory, however there has been a large number of psychological researches with Piaget’s. Another weakness in Vygotsky's theory is his failure to account for any developmental stages in children, and, more importantly, how such cognitive stages affect the ability to integrate and assimilate the inherent value in socialization (Vianna, 2006); application of each child’s ZPD may not be realistic.In addition to this weakness can be seen as some children may become dependent on scaffolding. Although Piaget theory is not a theory of education it has specific relevance to learning and practices in education. Piaget’s theory suggests that children are actively involved with the construction innate or individual knowledge and progress of themselves.From (Slavin 2005) study we can see that there are four teaching implications drawn from Piaget’s theory that can be applied; * A focus on the process of children's thinking, not just its products- teachers help the student to realise how they got the right answer instead of just simply checking for correction, thus including the child in the self-maturation.

* Children’s self-initiated and active in learning activities- to encourage children to be spontaneous in their thinking and interaction with the environment instead of being spoon feed information. A de-emphasis on practices aimed at making children adult like in their thinking. * Knowledge and applied understanding to individual differences in developmental progress-Children pass through the cognitive development stages at different individual rates; therefore teachers should adapt activities and lessons for individuals and groups rather than a class as a whole. Gravity Experiment Students are given a chance to use scientific principles by giving them a simple physical experiment to perform and write about in a report.Students must develop a principle based on experimentation and compare their results to that of scientists who have come before them.

Students drop objects of different masses at the same time from the same height to determine which objects fall faster. Students will be asked to form a hypothesis, a guess, as to what will happen prior to the actual experiment; they will be asked to conduct a series of tests. Students are required to record their findings. Finally they will write a lab report that includes their hypothesis, their process of experimentation, results and conclusions based on these results.