Lev Vygotsky (1978) believed that culture is the principal determinant of cognitive progress. Vygotsky was of the opinion that in constructivism, knowledge leads to further cognitive development and it is not possible to explain this on the basis of a single idea. Vygotsky also said that for intellectual development, social and practical activities are required. Cognitive development is the product of the dynamic relations between the individual and society. There is a mutual relation between individual and society and it has its impact on both individual and society. Social interaction influences cognitive development by creating cognitive structures and thinking processes. Educational implication of the theory of cognitive development:Teachers and students collaborate among themselves in learning and practicing four key skills: summarizing, questioning, clarifying, and predicting. The teachers role in the teaching-learning process is reduced over time.It provides scope for reciprocal teaching in which students play the roles of teacher and when they face difficulties, the teacher helps them as a facilitator.It provides learners scope to participate in creative activities and self-organization of ideas. It provides scope for new knowledge to be acquired and present knowledge to be expanded by the learner. In this approach, the teacher monitors and flexibly guides the students to the correct answer while encouraging critical thinking.It encourages teamwork and collaboration. So we can conclude that reciprocal teaching is based on the theory of cognitive development by Lev Vygotsky.Important Points Four Principles of Vygotsky:Children construct their own knowledge: It is rightly said that knowledge is not transferred passively, but is personally constructed by the individual. It means that for the transfer of knowledge, some medium is necessary on the basis of which knowledge can be received but every individual has his/her own way of perceiving the things and as per his/her perception or understanding, he/she constructs his/her knowledgeAcquisition of knowledge cannot take place without social context: It is correct to say that knowledge cannot be acquired without social context as a human being is a social being and he/she lives in society by following certain rules, norms of the society, and learn or expand his/her knowledge by interacting with the social surroundings. Learning is mediated: Mediated learning takes place when there is an interaction between a learner and a person who is more knowledgeable and helps the learners to modify stimuli and change their own cognitive structure. The person can be a parent, adult, grandparent, or peer and is called by Vygotsky a More Knowledgeable Other (MKO).Language plays a central role in cognitive development: Language is the means of communication and socialization. With the passage of time, it becomes a tool for cognitive development or thinking.