Student optimum learning level or zone of proximal development (ZPD) was first introduced in Vygotsky’s 1929 cultural-historical theory of psychological development. Vygotsky’s theory maintains that cognitive development includes (a) the processes of mastering the external means of cultural development and thinking in relation to language, writing, counting, and drawing, and (b) the processes of higher mental functions, which include the concepts of logical memory, categorical perception, voluntary attention, and conceptual thinking. Vygotsky believed that each student has a unique learning level or ZPD that is based on past interactions with adults, peers, culture, and environment. He defined ZPD as “the distance between the level of actual development, determined with the help of independently solved tasks, and the level of possible development, defined with the help of tasks solved by the child under the guidance of adults or in cooperation with the more intelligent peers” (Vygotsky, 1935/2011, p. 204).
ZPD is the bud or potential growth that can develop into ripened fruit or ownership of skill (Vygotsky, 1978), when feed the necessary nutrients. These are skills that are in the process of maturing and will need the assistance of an individual of higher 
cognitive processing level to complete. This is a student’s unique, ideal instructional or learning level that is constantly changing, as they work with individuals of higher cognitive processing levels and interact with their natural environment.
Student zone of proximal development (ZPD) is important to the scaffolding process, as student learning is most effective at this level. Instruction should begin just beyond what they already know or have mastered. Teachers use student ZPD to begin modeling how to complete a task not yet mastered. Teachers add scaffolds to assist the student(s) in learning new information and task completion. The scaffolds should be removed as student begins to show confidence or take ownership of unknown information. This may mean adding and subtracting the same or similar scaffolds before student becomes completely confident or has mastered the task. Student ZPD is most prevalent during the fading stage of the scaffolding process. Scaffolding is a process that includes three major stages—contingency, fading, and transfer of responsibility. The scaffolding process is described in further detail in my July 5th post—titled, Scaffolding Instruction.
Student ZPD can be located through assessment. Vygotsky suggested using assessments to measure student’s capabilities, that included (a) you demonstrate how to complete a task and observe the student mirror this demonstration, (b) you start a task and ask the student to complete the task, (c) ask the student to complete a task in collaboration with a higher functioning student, and (d) demonstrate metacognition in solving the task (Gredler, 2009). Teachers may also use formative, summative, and/or diagnostic assessments to help determine student’s approximate ZPD. Teachers can also use anecdotal notes or observations of student capabilities to help determine students ZPD. Teachers can also use student’s answer to questions about the current task posed by the teacher or person of higher cognitive ability to fine tune learner’s ZPD regarding a concept or task.
References
Gredler, M. (2009). Learning and Instruction Theory into Practice. Upper Saddle Creek, New Jersey: Pearson Education, Inc.
Vygotsky, L. (1929). The problem of the cultural development of the child II. Journal of Genetic Psychology, 36, 415-434. Vygotsky Reader, Blackwell. Retrieved from https://www.marxists.org/archive/vygotsky/works/1929/ cultural_development.htm
Vygotsky, L. S., & Kozulin, A. (1935/2011). The dynamics of the schoolchild’s mental development in relation to teaching and learning. Journal of Cognitive Education and Psychology, 10(2), 198-211. http://ia-cep.org/journal/jcep
Vygotsky, L. (1978). Interaction between learning and development. Mind and Society, 79-91. Cambridge, MA: Harvard University Press.
