Scaffolding and the zone of proximal development: A problematic relationship

For nearly four decades, a variety of social science disciplines have assumed that the zone of proximal development (ZPD) and the metaphor of scaffolding reflect more or less the same process. However, we will argue that any similarity is at best partial and at worst superficial. Equating the processes adds nothing to Vygotsky's general theory and in fact may weaken and dilute the robustness of the theory. To make the non-equivalence case, the paper first presents an overview of Vygotsky's approach to psychology that includes an expansive discussion of the ZPD not only as the activity in which instruction leads development, but also as the key to his approach to experimental research. This is followed by a critical review of the relevant statements that have appeared in the literature on the nature of scaffolding, its presumed link to the ZPD and that brings to the fore the inadequacies of the metaphor itself that disqualify it as an equivalent process. While the ZPD can be understood to include the kind of interaction that is described in the scaffolding literature, it is a much broader and far more robust process than scaffolding, as is made apparent when the two processes are compared, which is the focus of the concluding section of the article. In the comparison we summarize the analyses presented, especially with regard to the implications and relevance of the metaphors underlying each concept.