In this 6-year longitudinal study, 24 students were interviewed 11 times, between the ages of 9 and 15, to learn about their understanding of ecological processes. Students were asked about their conceptions of three topics: (a) the conditions for life of plants in a sealed transparent container, (b) the decomposition of leaves on the ground, and (c) the role of flowers in plant reproduction. At ages 15 and 19, the students listened to what they had said about these topics as 11? and 15?year?olds. They were then asked to state how they thought their understanding had developed. The interviews were analysed using principles from Ausubel's (1978) theory of meaningful learning. Characteristic individual themes in the students? conceptions could be followed year by year, especially with respect to their understanding of the cycles in nature. After the students had listened to their earlier interviews, they would often refer to experiences from an early age that they mentioned again and again. The analysis of students? descriptions of themselves as learners also made it possible to discern their different views of learning about ecological processes. In this 6?year longitudinal study, 24 students were interviewed 11 times, between the ages of 9 and 15, to learn about their understanding of ecological processes. Students were asked about their conceptions of three topics: (a) the conditions for life of plants in a sealed transparent container, (b) the decomposition of leaves on the ground, and (c) the role of flowers in plant reproduction. At ages 15 and 19, the students listened to what they had said about these topics as 11? and 15?year?olds. They were then asked to state how they thought their understanding had developed. The interviews were analysed using principles from Ausubel's (1978) theory of meaningful learning. Characteristic individual themes in the students? conceptions could be followed year by year, especially with respect to their understanding of the cycles in nature. After the students had listened to their earlier interviews, they would often refer to experiences from an early age that they mentioned again and again. The analysis of students? descriptions of themselves as learners also made it possible to discern their different views of learning about ecological processes.