In a 1-hour teaching interview, 20 children (aged 7 to 11) discovered how to tell whether objects might be made of the same material by using ratios of measures of weight and size. We examine progress in the children's reasoning about measurement and proportional relations, as well as design features of instruments, materials, and tasks crafted to…

This paper presents a model of how children generate concrete concepts from perception through processes of differentiation and integration. The model informs the design of a novel methodology ("evolutionary maps" or "emaps"), whose implementation on certain domains unfolds the web of itineraries that children may follow in the…

Previous research indicates children reason in different ways about horizontal motion and motion in fall. At the same time, their understanding of motion down inclines appears to result from an interaction between horizontal and vertical motion understanding. However, this interaction is still poorly understood. Understanding of speed change may…

This dissertation explored beliefs about learning from multiple related visual representations in science, and compared beliefs to learning outcomes. Three research questions were explored: 1) What beliefs do pre-service teachers, non-educators and children have about learning from visual representations? 2) What format of presenting those…

The development of a diachronic conception of biology has rarely been explored during childhood, except by Maurice-Naville and Montangero (1992). The aim of the present study was to further explore this issue. In the course of an interview, 163 children aged between 6 and 11 expressed their diachronic conceptions of the growth and death of several…

Teleo-functional explanations account for objects in terms of purpose, helping us understand objects such as pencils (for writing) and body parts such as ears (for hearing). Western-educated adults restrict teleo-functional attributions to artifact, biological, and behavioral phenomena, considering such explanations less appropriate for nonliving…

Reflects on a number of topics relating to science fiction, including the power of good science fiction to spark imaginations and provoke serious thought, the role of women in science fiction, childhood experiences that stimulated the author's thought processes, and the author's experiences as a science fiction writer. (ET)