Constructionism supports the constructivist viewpoint--that the learner is an active builder of knowledge. However, it emphasizes the particular constructions of external artifacts that are shared by learners. Although learners can construct and present knowledge or meanings without producing external products, the processes of construction are more evident when learners produce through social interaction with others and share representations of their understanding and thoughts.

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OLPC interpretation of Constructionism: http://wiki.laptop.org/go/Constructionism