Jean Piaget formalized the theory of constructivism which says that people construct their own understanding through experiences. According to Piaget, individuals learn through assimilation, where new information is incorporated into existing knowledge, and accommodation, where existing knowledge must change to accept new information. Constructivism involves active and discovery learning where students solve problems and develop skills through group discussions and synthesis of ideas. The teacher helps students develop skills and attitudes by focusing on knowledge construction rather than reproduction through authentic tasks and problem-based thinking that requires reflection.