Zone of Proximal Development ZPD

Vygostsky (1978) defined the Zone of Proximal Development (ZPD) as the difference between a child's actual developmental level as determined by independent problem-solving and the level of potential development as determinded through problem-solving under adult guidance or in collaboration with more capable peers.

According to Vygotsky, essential feature of learning is that it creates the Zone of Proximal Development (ZPD). Learning (activity) awakens a variety of internal developmental processes that are able to operate only when the learner is interacting with people in his environment and in cooperation with his peers.

Maturing and developing mental functions of a learner must be fostered and assessed through collaborative, not independent or isolated activities. He claimed that the intellectual skills learners acquire are directly related to how they interact with others in specific problem-solving environments. Learners internalize and transform the help they receive from others and eventually use these same means of guidance to direct their subsequent problem-solving behaviours. Therefore, the nature of social transactions is central to a ZPD analysis. In this way, what learners can perform collaboratively or with assistance today they can perform independently and competently tomorrow.

He argued that standard tests (e.g. IQ test) in our education system give a picture only of completed development. They assess mental functioning that has already matured, fossified. The information from these assessments is of little use in the important task of instruction (teaching and learning). He believed it was the duty of school system to bring out the full potential of each student. The task cannot be accomplished by assuming that completed development fully specifies a trajectory for the future. The standardised assessment strategy leads to a false understanding of the relation between development and instruction, which converts the school system into a vast selection machine.

However, we should think of ZPD as a characteristic not solely of the learning or teaching but of the student engaged in collaborative activity within specific social environments. The focus is on the social system within which we hope students learn, with the understanding that this social system is mutually and actively created by teacher and students.

ZPD reminds us that educational settings are social creations. They are socially constituted, and they can be socially changed. It warns us how easy it is to under-estimate students' and teachers' abilities when we analyze them in isolation. It points to the use of social and cultural resources that represent our primary tools, as human beings, for mediating and promoting change.

Internalization and Externalization

AT describes the mechanisms underlying the mental processes as internalization and externalization.

Mental processes such as remembering, recalling, analyzing, planning, imaginings, simulating, calculating, etc. are derived from external actions through the course of internalization. We "remember and recall" or "analyze" when we need to respond to some people or things. We remember and recall things "selectively" subjected to our interest, needs, and the context and state we are in. We analyze using our prior knowledge and experience, values and beliefs, and come to an "understanding". We then manifest (externalize) these mental processes by peforming some actions, to verify or correct our memory or understanding.

Internalization is the transformation of external activities into internal ones. Hands-on activities and tools are curcial for internalization. Internalization provides a means for people to try potential interactions with reality without performing actual manipulation with real objects. e.g. mental calculations, simulations, imagining, etc. The process of internalization can help to identify an optimal way to perform action before performing the action externally.

Externalization transforms intenal activities into external ones. Externalization is necessary when an internalized activities need to be verified or corrected. It is important when a collaboration between several people requires their activities to be performed externally in order to be coordinated.

AT holds that internal activities cannot be understood if they are analyzed separately, in isolation from external activities, because they are mutual transformations between these two kinds of activites.

It is the constant transformation between external and internal activities that is the very basis of human cognition and practice.

Engeström's Expansive Triangle

(Extracted from Learning by Expanding (1987))
Engeström holds that this model is the smallest and most simple structural form that still preserves the essential unity and integral quality of any human activity. With the help of this model, activity can be analyzed in its inner dynamic relations and historical change. It is a useful tool for identifying the deep seated contradictions that give rise to surface level discoordination and conflict. Activity Theory sees these contradictions as sources of learning and development. Real practices are practically always in the process of working through some of such contradictions even though these are experienced negatively by participants who always wish to see the activity system "running smoothly". But change is the only constant in a system.

• An activity is actually a system whole in the sense that all elements have a relationship to other elements. It is the fundamental context of study.


• The relation between subject and object is mediated by tools (or instruments), that between subject and community is mediated by rules (norms or constraints), and that between object and community is mediated by division of labor.


• Each of the mediating elements is historically formed and opened to further development. Ever since an activity is formed, the corresponding mediating elements are continuously reconstructed. This development is driven by different contradictions, it is not a smooth and linear process but uneven and discontinuous one.


• An acivity has an active subject (an individual or collective), who understands the object (motive) of the activity. However, not all participants (community) invovled in an activity necessarily understand the motive of the activity in which they are participating or even recognize the existence of one.


• As the contradictions (structural tensions) of an activity system are aggravated over a period of time, some individual participants begin to question and deviate from its established norms.