The zone of proximal development is a theory advanced by Russian educational psychologist Lev Vygotsky. The zone of proximal development refers to the difference between what a child can do on his own and the help he needs from someone with recognized expertise in a subject matter. Vygotsky's theory involves the necessity of language, social interaction and group work for childhood learning. The zone helps teachers identify areas in which students need instruction. It is divided into four distinct stages.

Assisted Performance

The first stage takes place when a child is first learning a new subject matter or skill and requires help from someone with greater knowledge than his own. Typically, the person who assists the child is someone in a position of authority, such as a teacher, parent or coach who has developed an expertise in the subject area or skill. The assisted child learns through a series of instructional methods that include lecture, question-and-answer, problem solving and positive reinforcement.

Unassisted Performance

As a child gains understanding of the new subject or skill, she moves into the second stage, in which she performs tasks without relying on the person who was assisting her. Though she may not have gained mastery, she is now confident enough to work through the task by herself, even if she makes occasional mistakes. The second stage is still considered a beginning stage because the child has not attained full capacity.

Full Internalization

In the third stage, a student's knowledge reaches the point where performance is automatic and fully developed. Any doubts are gone during this stage, and the student has internalized the skills necessary to perform the task with proficiency. Expert assistance or tutelage is not required or needed, and in fact the student may resent the intrusion or advice of the expert now that he has fully developed his own level of expertise.


The fourth and final stage typically occurs later in life when the student becomes an adult and loses the ability to perform at a proficient level. At that point, she must go through the development process again to restore knowledge and skills she has lost. Reasons for de-automization may include personal crisis, sudden trauma, gradual erosion of skills due to age, and major life changes. Self-evaluation and continuing education are measures that may help delay de-automization, but it is an inevitable occurrence that requires individuals to regress to the beginning of the learning cycle to regain mastery.