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A sample of 100 students from junior high school physical science, high school chemistry, and introductory college chemistry were examined for understanding of five chemistry concepts. The concepts addressed were chemical change, dissolution of a solid in water, conservation of atoms, periodicity, and phase change. The amount of experience with the concepts (grade level) and reasoning ability (developmental level) were examined as possible sources of variation in student understanding. Differences in understanding with respect to grade level were found to be significant for the concepts of chemical change, dissolution of a solid, conservation of atoms, and periodicity. However, few of the students in the college chemistry sample exhibited sound understanding of chemical change, periodicity, or phase change. The use of particulate terms (atoms, ions, molecules) increased across the grade levels. Reasoning ability proved to be a significant factor for student understanding of conservation of atoms and periodicity. An examination of the number and types of misconceptions across the grade levels revealed several interesting patterns and suggested sources for the students' alternative conceptions. 相似文献
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This paper is part of a larger work on the history, philosophy and utilisation of pendulum motion studies (Matthews 2000). The paper deals with the fate of Christiaan Huygens 1673 proposal to use the length of a seconds pendulum (effectively one metre) as a universal, natural and objective standard of length. This is something which, if it had been adopted, would have been of inestimable scientific, commercial and cultural benefit. Why it was not originally adopted in the late seventeenth century, and why it was again rejected in the late eighteenth century (1795) when the Revolutionary Assembly in France adopted the metric system with the metre being defined as one ten-millionth of the quarter meridan distance – raise interesting questions about the methodology and politics of science. Given that pendulum motion is a standard component of all science courses throughout the world, and given that most science education reforms, including the US National Science Education Standards and recent Australian state reforms, require that something of the big picture of science be conveyed to students (the relationship of science to culture, commerce, history and philosophy) – it is suggested that these educational goals can be advanced by teaching about the fate of Huygens' proposal. 相似文献
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Brown Scott W. Boyer Mark A. Mayall Hayley J. Johnson Paula R. Meng Lin Butler Michael J. Weir Kimberly Florea Natalie Hernandez Magnolia Reis Sally 《Instructional Science》2003,31(4-5):255-276
The GlobalEd Project employs a technology richenvironment for high school students who wishto participate in a simulation of internationalrelations and negotiation. A simulationconsists of negotiations on a variety ofinternational policy issues conducted bystudents from 10–15 schools through anInternet-based interface. This study reportsthe findings of 234 high school participants'changes in academic and technologyself-efficacy skills, as well as knowledge,attitudes and behaviors related to academicpreparation and performance, the use ofeducational technology, and associated outcomesfrom participating in a simulation ofinternational relations. The results arediscussed in terms of the current literature onself-efficacy and gender differences incognitive process. 相似文献