A. Theory of Cognitive DevelopmentIn a general sense the theory of cognitive development is not just a single theory but a set of theories offered by a number of cognitive psychologists over the last century. In summary, however, cognitive development is the process by which learning develops through the construction of thinking processes, memory, problem solving, decision making and spans the lifespan from childhood to adulthood, but learning doesn't necessarily stop at adulthood. This construction process is clinically known as “Constructivism”. In constructivism it is not the world or society that is developing a child but it is the child who acquires information and builds himself with the information that the society in which he lives has accumulated in previous generations. Jean Piaget (1896-1980) The theory of constructivism states that children are capable of learning only up to a certain level of development and once they reach a biological milestone, they will be able to acquire new information and knowledge that adds to those already acquired. If the level of knowledge goes beyond a child's current level of understanding, they will not be able to understand what is being presented to them, and it is the biology of the brain that determines when a child will be able to continue to the next and higher level of understanding. information. Piaget placed these markers or “take off” points at ages 18 months, 7 years, and 12 years. This theory is very similar to building a house where each phase of construction must be completed before the next phase can begin, hence the term constructivism. In other words, society can only give a certain level of knowledge to a child and anything higher would be...... half of the paper ...... ch 25, 2011 http://www.simplypsychology. org/vygotsky. htmlTheory of social development (L. Vygotsky). Explorations in learning and education: The theory to practice database. Retrieved March 26, 2011 http://tip.psychology.org/vygotsky.htmlBeaumie Kim, University of Georgia. (2006). Social constructivism. Retrieved March 15, 2011 http://projects.coe.uga.edu/epltt/index.php?title=Social_ConstructivismEducational Implications of Piaget's Theory. PEARSON. Retrieved March 26, 2011 http://wps.ablongman.com/ab_slavin_edpsych_8/38/9951/2547688.cw/content/index.htmlClassroom Applications of Vygotsky's Theory. PEARSON. Retrieved March 26, 2011 http://wps.ablongman.com/ab_slavin_edpsych_8/38/9951/2547689.cw/content/index.htmlVygotsky, L. S. (1978). Mind and society: the development of higher mental processes. Cambridge, MA: Harvard University Press.