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991.
John Jerrim Luis Alejandro Lopez-Agudo Oscar D. Marcenaro-Gutierrez 《European Journal of Education》2020,55(2):248-260
The association between time devoted to homework and children's academic achievement has long been an issue of great debate. A small number of mainly correlational studies have been conducted into this issue in a primary school setting, but have produced somewhat mixed results. In this paper we contribute to this literature by investigating the relationship between time spent upon homework and children's outcomes across 24 countries. By using a student fixed-effects approach, capturing differences in homework time amongst the same student across different school subjects, we argue that our results are likely to be subject to less confounding than much of the existing literature. We find little evidence that the amount of homework time primary school children are assigned is related to their academic achievement. This holds true across a large number of countries, survives various robustness tests and does not vary by gender or socio-economic status. We interpret this finding as suggesting that the homework assigned to primary school pupils may not be adequate to produce a positive association, and needs be improved if this time-consuming activity is ever going to bring benefits for children's academic achievement. 相似文献
992.
993.
This Special Topic section of Biomicrofluidics on "Surface Modification, Wetting, and Biological Interfaces," is discussed. The topic is very timely and one that is tremendously relevant to the microfluidics and nanofluidics community. 相似文献
994.
Carson V Spence JC Cutumisu N Boule N Edwards J 《Research quarterly for exercise and sport》2010,81(4):392-399
Little research has examined seasonal differences in physical activity (PA) levels among children. Proxy reports of PA were completed by 1,715 parents on their children in Edmonton, Alberta, Canada. Total PA (TPA) minutes were calculated, and each participant was classified as active, somewhat active, or inactive. Logistic regression models were conducted to examine associations between PA status and seasons. Significant seasonal differences were observed for TPA, weekday PA, weekend PA, and active play. Children were significantly more likely to be physically active in the summer and spring and somewhat physically active in the summer and fall, relative to winter Children living in cold climates are less likely to be physically active in the winter. 相似文献
995.
996.
<正>快速问答:说出一个中国的名牌。日本有索尼。墨西哥有科罗娜啤酒(Corona)。德国有宝马。韩国有三星。那中国有……?假如被这个问题难住了,你不是唯一答不出来的人。这个问题对中国 相似文献
997.
Research in the teaching and learning of evolutionary biology has revealed persistent difficulties in student understanding of fundamental Darwinian concepts. These difficulties may be traced, in part, to science instruction that is based on philosophical conceptions of science that are no longer viewed as adequately characterizing the diverse nature of scientific practice, especially in evolutionary biology. This mismatch between evolution as practiced and the nature of science as perceived by researchers and educators has a long history extending back to the publication of Darwin's theory of natural selection. An examination of how this theory was received by the scientific community of the time may provide insight into some of the difficulties that students have today in learning these important biological concepts. The primary difficulties center around issues of metaphysics and scientific method, aspects of the nature of science too often ignored in science education. Our intent is not to offer a specific course of action to remedy the problems educators currently face, but rather to suggest an alternative path one might take to eventually reach a solution. That path, we argue, should include the use of broader models of science that incorporate these elements of scientific practice to structure teaching and education research in evolution. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 1069–1089, 1998 相似文献
998.
The purpose of this investigation was to evaluate the construct validity of the parent version of the Penn Interactive Peer Play Scale (PIPPS) and to compare it with the teacher version. PIPPS were collected on 297 urban Head Start children. The Parent PIPPS replicated the three-factor solution found with the teacher version, supporting the following constructs of peer play: Play Interaction, Play Disruption, and Play Disconnection. Factor matching and canonical correlational analyses examining the relationship between the parent and teacher versions of the PIPPS revealed significant one-to-one matches between hypothesized like factors. Additionally, analyses of overlapping variance between versions indicated a significant degree of overlap. Implications of the findings for involvement of parents in the assessment process and research on the continuity and discontinuity between home and school environments for low-income, urban children were discussed. 相似文献
999.
放肆无礼万岁!它是我在这个世界上的守护神.
爱因斯坦致米列娃·马里奇,1901年12月12日[1]
我寻求孤独,随后又在孤独中默默忧伤.
爱因斯坦致“妈妈“温特勒,1897年5月21日[2]
…… 相似文献
1000.