Vlev vygotsky's sociocultural theory emphasizes that is (are) necessary for children to acquire the ways of thinking and behaving that make up a community's culture.

I believe the right answer is social interaction.

Lev Vygotsky's theories stress the fundamental role of social interaction in the development of cognition (Vygotsky, 1978), as he believed strongly that community plays a central role in the process of "making meaning."  

Vygotsky’s main assertion was that children are entrenched in different sociocultural contexts and their cognitive development is advanced through social interaction with more skilled individuals. Vygotsky (1978) states: “Every function in the child’s cultural development appears twice: first, on the social level, and later, on the individual level; first, between people (interpsychological) and then inside the child (intrapsychological). This applies equally to voluntary attention, to logical memory, and to the formation of concepts. All the higher functions originate as actual relationships between individuals.” (p57).

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