Constructivism is an educational theory that emphasizes hands-on learning and the construction of knowledge through experiences. According to constructivism, learning occurs as learners are actively involved in a process of meaning and knowledge construction rather than passively receiving information. Key aspects of constructivism include: students learning through exploring and interacting with their environment; the teacher acting as a facilitator rather than lecturer; and knowledge being built upon previous knowledge and experiences. Major contributors to constructivism include Piaget, Vygotsky, and Bruner.