Conferences

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ConferencesCongrés

     

Recent Conferences

Atomic theory or the nature of matter is a principal concept in science and science education. This has, however, been complicated by the difficulty students have in learning the concept and the subsequent construction of many alternative models. To understand better the conceptual barriers to learning atomic structure, this study explores the troublesome nature of this fundamental scientific concept. In order to illustrate the distinction of student understanding by threshold barriers, this study chose three particularly high‐achieving students from an original interview sample of 20 students who were selected from an introductory college chemistry course. The pre‐course and post‐course interview responses were examined and compared in detail. This study considers the concepts of ‘probability’ and ‘energy quantization’ to both describe the structure of the threshold of understanding students’ need to negotiate in their construction of the target model of atomic structure. In this respect, this study suggests atomic structure as a possible threshold concept for further study in science. Identifying the nature and structure of the threshold of understanding confronting students, and analyzing the troublesomeness of atomic structure, provides valuable information for understanding student learning difficulties, and insight into how they may be addressed.     

Forthcoming Conferences

Thirty 14‐15‐year‐old pupils were taught about the effect of temperature and pressure on a gaseous reaction at equilibrium. Two problems were then given to the pupils and a word association test on a small number of carefully chosen stimulus words was administered in the context of the problems. The pupils were finally interviewed about what they had done in the tests. The results of all of the tests were analysed and compared for evidence of perception and strategy.

Various strategies were found to have been used by the pupils: one based on the formally correct perception of Le Chatelier's rule, one based on a perception in which the speed of a reaction is the factor that governs position of equilibrium (this was the major incorrect strategy), one that uses spurious analogies with more familiar factors (such as ‘catalyst') and one that reflects only superficial learning with no evidence of Le Chatelier's principle.

Comparisons with the classroom tests and the interview data revealed that about 60% of the word association test results produced responses that were criterial for the problem‐solving strategies adopted by the pupils, both correct and incorrect. The results show that this type of word association offers a means of unobtrusive, formative testing which, with experience, could be used to anticipate learning problems in science lessons.