Formalization of the theory of constructivism is generally attributed to Jean Piaget, who articulated mechanisms by which knowledge is internalized by learners. He suggested that through processes of accommodation and assimilation, individuals construct new knowledge from their experiences. Assimilation occurs when individuals' experiences are aligned with their internal representation of the world. They assimilate the new experience into an already existing framework. Accommodation is the process of reframing one's mental representation of the external world to fit new experiences. Accommodation can be understood as the mechanism by which failure leads to learning. When we act on the expectation that the world operates in one way and it violates our expectations, we often fail. By accommodating this new experience and reframing our model of the way the world works, we learn from the experience of failure.
It is important to note that constructivism itself does not suggest one particular pedagogy. In fact, constructivism describes how learning happens, regardless of whether the learner is leveraging their experiences to understand a lecture or attempting to design a model airplane. In both cases, the theory of constructivism suggests that learners construct knowledge. Constructivism as a description of human cognition is often confused with pedagogic approaches that promote learning by doing.