This study of personal context and continuity in twenty-three pupils' thinking builds upon data from a longitudinal study of pupils' conceptualisations of conditions for life, decomposition and the role of the flower. Each pupil was interviewed eleven times between the age of 9-15. At age 15 and 19, each pupil listened to what they had said four years earlier and described how they thought their understanding had developed. The occurrence of characteristic, individual elements of a content or structural nature can be followed through the interviews, year by year. As 15 and 19-year-olds, the pupils could recognise statements in the interviews as results of experiences from an early age. It is possible to follow a characteristic, individual theme in most of the interviews. Conceptions developed at an early age appeared to be important to future conceptual development. Early introduction of some scientific concepts would help pupils to develop a deeper understanding.