It is proposed that pupils internalize each conceptual unit as an isolated episode. Thus, the cognitive structures in the minds of the pupils are likely to be a heterogeneous assembly of episodes without much intercommunication between them. That this form of conceptualization may generate manifest alternative conceptions, when a demand is made for a simultaneous utilization of various episodes, is demonstrated in the concept domain of inertia, force and motion. Implications of this for teaching and strategies for the improvement of the teaching‐‐learning process are suggested.