Varda Bar

Stages of children's views about evaporation

This paper presents research results which reveal a well‐defined hierarchy of views children employ about evaporation and relative science curriculum topics in elementary school in Israel. The sequential change of these views was studied, described and scaled on the age span of five to 14. Factors influencing this evolution and its testing were evaluated. The extent to which the method of research and context environment might influence the research results were also studied. The conceptual change of views regarding evaporation, taking place in childrens minds, shows a clear correlation with their cognitive development, their progress in operative knowledge‐namely, the usage of the conservation principle, and the adoption of an abstract model for air.

Motion implies force: where to expect vestiges of the misconception?

The reported progress of post‐instruction students in understanding the force‐motion relationship in classical mechanics might be partially caused by the kind of questions used in tests. Citing a parallelism with historical progress towards correct force‐motion understanding, this research points to the factors which might help to discover the vestiges of the naive views of motion in novice students, and explains the motivation of their ‘regression’ to the motion‐implies‐force preconception. Among the factors are the novel context of qualitative questions, and situations of nonzero acceleration, especially when velocity and force are unparallel. The understanding of these factors should help to foster genuine progress in students’ conceptual understanding as well as to provide its reliable check. The research sample included pre‐ and post‐instructional high‐school students, students of a University Pre‐academic Study Department and preservice teachers in a Technology Teachers College.

Children's ideas about action at a distance

Childrens ideas about action at a distance are analysed according to the commonsense theory. These ideas can be organized around three presuppositions which express concrete realizations of the abstract idea of interaction at a distance. The presuppositions are concerned with the uniqueness of earth, the need for connection between objects interacting at a distance, and how various forces support and focus each other. These ideas do not form a self‐consistent set of axioms to be applied coherently, but rather form a guiding framework. The chosen presuppositions are context dependent and related to the different environments of earth, a satellite, the moon and outer space. Support is preferred over connection. The relevance of these findings for instruction are discussed.

Children's operational knowledge about weight

This study explores childrens knowledge regarding weight in the age span of five to sixteen years. It appears that childrens views develop gradually from the tactile experiences. Thus, such schemes as ‘weight‐is‐a‐pressing‐force’, ‘weight‐is‐possessed‐exclusively‐by‐heavy‐objects’, ‘suspended‐substances‐are‐weightless’, ‘weight‐is‐heaviness‐to‐hold/move’, and others, are intuitively constructed at a young age. Childrens applications of these schemata might be mutually contradictory in different physical situations, being gradually, pushed by the ideas of weight conservation. As the transition of the knowledge status is continuous and not synchronized between different aspects of reality, the regular classification of children between ‘conservers’ and ‘nonconservers’ of weight is rather imprecise. Children can simultaneously employ different operational schemata and concept images with regard to the same physical concept or phenomenon. The study implies that the identification of weight with gravitation...

Pupils’ Image of ‘the Scientist’ among Two Communities in Israel: A comparative study

The image of ‘the scientist’ and its effect on the willingness to be a scientist and to follow a career in science were investigated in two different cultural populations of elementary and junior high school pupils in Israel: Hebrew‐speaking (secular) pupils (N = 390) and Arabic‐speaking Bedouin pupils (N = 185). Five different tools were employed in our investigation (naming scientists, pictorial representation of the scientist (‘Draw‐a‐Scientist‐Test’), statements regarding the characteristics of the scientist, reasons for wanting/not wanting or being able/being unable to be scientists, and sources of knowledge regarding the scientist’s image). The image held by Hebrew pupils was similar to those held by western pupils found in previous research, but some details were more elaborate (due to the fact that many different tools were employed here). However, the image held by the Arabic pupils differed from that found in previous research. This image had a strong ethnical trend, with Golden Age Muslim scientists’ names dominating name lists, and drawings of traditional Muslim figures. Another image found in their drawings was of a scientist admired as a teacher, emphasising the Bedouin school’s formal culture. The theory of modernity will be a useful analytical tool to judge the results of the investigation, whether the population is supposed to be (or is close to) a modern population and whether it does not, definitely, fall under this definition (see Methods and Discussion).

Introducing mechanics at the elementary school

Elementary school children do not identify weight and force. But they can use the ratio between weights to compare forces. This finding is used to develop a teaching unit.