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The purpose of this study was to describe the development of elementary students' skill in making predictions and of their understanding of what predicting means. The study involved observing and assessing the performance of 167 children on the Physical Manipulation Test (PMT), a test involving the manipulation of science materials and equipment. Children were interviewed about what they understand predicting to mean, how they use it at school and at home, and why they think it is important. For each of the seven topics tested, even the youngest children were able to offer predictions. Accuracy varied with the topic, increasing between Grades 1 and 4 and leveling off after that. The increase in skill involved children's growing ability to attend to patterns discerned through their own observations. Four levels in the development of predicting skill, as it relates to particular topics, are described. Children's understanding of predicting showed steady improvement through Grade 6. Children's awareness of their use of predicting at school and at home, and their ability to explain the importance of predicting, also increased through Grades 1 to 6, with a spurt at Grade 4. Children understood predicting to be an internal process in which one uses knowledge to anticipate a future event; they regarded predicting as an important way of being intellectually involved with the world.  相似文献   
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The project of studying children in order to understand them, which lies at the heart of contemporary thinking about children and their education, is misconceived. It rests, jrst of all, upon a false belief that we can only come to know something properly by deliberately and systematically pursuing knowledge of it. Secondly, it offers a paradigm of knowing children which justifies parents and teachers in not giving themselves to children. By re-interpreting the problems that adults experience with children as technical, as arising from lack of information about them, it ignores the personal and moral dimension of adults' relations with children and thus further alienates them from one another.  相似文献   
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This article discusses the changing relationships of authors and publishers, the current trends and challenges they face, and the direction of these relationships in the future. As the STM publishing industry finds itself in the midst of significant technological and economic changes, this article provides background to these changes and looks at the key elements, including open access business development, institutional repository trends, and emerging public financing policies in the future.  相似文献   
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Do students today know less than their parents or grandparents did as students? Are they being academically outclassed by students of other nations? Or have ideologically driven policy makers painted an unnecessarily negative picture of student achievement?  相似文献   
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This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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