Lev Vygotsky

Cognitive Development: The study of how children acquire the ability to learn, think, reason, communicate, and remember.

Social Constructivism: A sociological theory that argues that people create or construct their own perceptions of reality based on their experiences and interactions with others.

Zone of Proximal Development: The difference between what learners can do without help and what they can achieve with guidance from someone more knowledgeable.