Constructivist approach teaching methods are based on constructivist learning theory. John Dewey and Jean Piaget researched childhood development and education; both were very influential in the development of informal education. Dewey’s idea of influential education suggests that education must engage with and enlarge exploration of thinking and reflection associated with the role of educators. Contrary to this, Piaget argued that we learn by expanding our knowledge by experiences which are generated through play from infancy to adulthood which are necessary for learning. Both theories are now encompassed by the broader movement of progressive education. Constructivist learning theory states that all knowledge is constructed from a base of prior knowledge. As such, children are not to be treated as a blank slate, and make sense of classroom material in the context of his or her current knowledge.