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871.
H M Breland 《Child development》1974,45(4):1011-1019
Two samples of National Merit Scholarship participants test in 1962 and the entire population of almost 800,000 participants tested in 1965 were examined. Consistent effects in all 3 groups were observed with respect to both birth order and family size (1st born and those of smaller families scored higher). Control of both socioeconomic variables and maternal age, by analysis of variance as well as by analysis of covariance, failed to alter the relationships. Stepdown analyses suggested that the effects were due to a verbal component and that no differences were attributable to nonverbal factors. Mean test scores were computed for detailed sibship configurations based on birth order, family size, sibling spacing, and sibling sex.  相似文献   
872.
A systems-based classroom intervention on environmental education was designed for seventh grade students; the results were evaluated to see its impact on the development of systems thinking skills and standard science achievement and whether the systems approach is a more effective way to teach environmental issues that are dynamic and complex. A quasi-experimental methodology was used to compare performances of the participants in various dimensions, including systems thinking skills, competence in dynamic environmental problem solving and success in science achievement tests. The same pre-, post- and delayed tests were used with both the comparison and experimental groups in the same public middle school in Istanbul. Classroom activities designed for the comparison group (N = 20) followed the directives of the Science and Technology Curriculum, while the experimental group (N = 22) covered the same subject matter through activities benefiting from systems tools and representations such as behaviour over time graphs, causal loop diagrams, stock-flow structures and hands-on dynamic modelling. After a one-month systems-based instruction, the experimental group demonstrated significantly better systems thinking and dynamic environmental problem solving skills. Achievement in dynamic problem solving was found to be relatively stable over time. However, standard science achievement did not improve at all. This paper focuses on the quantitative analysis of the results, the weaknesses of the curriculum and educational implications.  相似文献   
873.
This article documents minority youth sense-making around the concept of diversity and the founding of a youth activist group that seeks spaces for policy thinking and protesting against racial inequalities in selective enrollment schools. Utilizing the sociological theory of racial formation and the concept of racial projects (Omi and Winant in Racial formation in the United States, 3rd edn, Routledge, New York, 2014), this article draws on data from a critical ethnography. The author argues that youth activists offer a critical perspective for researchers and policy-makers in the face of neoliberal school choice policy. Findings reveal that youth activists understand a lack of diversity as racial imbalance in high status schools, and that they expose structural inequalities that are embedded in policy structures and processes such as selective enrollment high schools. Implications are discussed to show how re-conceptualizing policy as a racial formation can bring structural and institutional racist practices into view in hopes of transforming district policies to offer access to high quality schools for all students.  相似文献   
874.
This explanatory sequential mixed methods study investigated the writing feedback perceptions of middle and high school students (N = 598). The predictive and mediational roles of writing self-efficacy and perceptions of writing feedback on student writing self-regulation aptitude were examined using mediation regression analysis. To augment the quantitative findings, the explanations students provided for either liking or disliking writing feedback were explored using open-ended questions. Quantitative findings revealed that students’ perceptions of the feedback they receive about their writing partially mediated the relationship between writing self-efficacy and writing self-regulation aptitude. Qualitative data suggested ways in which students perceive writing feedback—both positive and negative. Collectively, the quantitative and qualitative data illustrate the influential role writing feedback perceptions plays in middle and high school student writing motivation and self-regulation beliefs.  相似文献   
875.
Given that gestures may provide access to transitions in cognitive development, preschoolers' performance on standard tasks was compared with their performance on a new gesture false belief task. Experiment 1 confirmed that children (N=45, M age=54 months) responded consistently on two gesture tasks and that there is dramatic improvement on both the gesture false belief task and a standard task from ages 3 to 5. In 2 subsequent experiments focusing on children in transition with respect to understanding false beliefs (Ns=34 and 70, M age=48 months), there was a significant advantage of gesture over standard and novel verbal-response tasks. Iconic gesture may facilitate reasoning about opaque mental states in children who are rapidly developing concepts of mind.  相似文献   
876.
In Modeling Theory in Science Education, Halloun (2004) adopts the word ‘paradigm’, but his use of the term is radically different from that of Kuhn. In this paper, I explore some of the differences between Kuhn’s paradigms and Halloun’s paradigms. Where Kuhn’s paradigms are public, community-defining exemplars of practice, Halloun’s paradigms are private, individualized ways of thinking. Where Kuhn writes of the paradigm shift as a revolutionary, vision-altering conversion experience, Halloun writes of a gradual evolution from one way of thinking to another and an easy back-and-forth switch between paradigms. Since Kuhn’s paradigms are self-enclosed and incommensurable, there is no objective standard by which one paradigm can be shown to be superior to the other. But Halloun uses ‘viability’ as a standard for paradigm choice. Underlying all of this is the more basic question of whether the history of science is an appropriate metaphor for student progress in the classroom. I conclude with some brief thoughts on this question.  相似文献   
877.
There is now widespread recognition that digital technologies, particularly portable hand held devices capable of Internet connection, present opportunities and challenges to the way in which student learning is organized in schools, colleges and institutions of higher education in the 21st Century. Traxler, Journal of the Research Centre for Educational Technology, 6(1), 3–15 (2010) suggests such devices are pervasive and ubiquitous, conspicuous and unobtrusive, noteworthy and taken-for-granted with everyone typically owning one, using one and often having more than one. As a consequence it has been argued that the availability of such devices, controlled mainly by the student and not the teacher, has the potential to change the traditional dynamics and pedagogical patterns of the learning environment (Burden et al. 2012). Education institutions, however, typically remain organized around spatial and temporal considerations such as buildings, timetables, calendars and internal structures which are designed to classify and manage students. In the case study reported here students and faculty teaching staff from the College of Education in the Kuwait University were surveyed in order to assess their access to such technologies, their capability to use them effectively in support of achieving planned learning outcomes and the implications for change that could emanate from such findings.  相似文献   
878.
879.
1 hypothesis about children's developing conception of the mind is that preschoolers are limited to an understanding that persons have internal, mental contents like thoughts and beliefs, whereas older children and adults conceive of the mind itself as an independent, active structure or processor. Adults' conception of the mind in this independent active fashion seems evident in their use of personified mental metaphor (e.g., "My mind tricked me"). 3 studies examined the development and consolidation of this active, personified view. Study 1 provided an analysis of natural language data regarding 1 child's uses of vision words such as see and look from age 2 1/2 to 8 years. We examined the child's use of such words to refer literally to perception (e.g., "I see the TV") and also to refer nonliterally to active mental processes such as comprehension and inference (e.g., "I see what you mean"). Studies 2 and 3 examined 6-, 8-, and 10-year-olds' comprehension and production of mental metaphors. In a metaphor comprehension task, we asked children to interpret personified metaphoric statements about the mind (e.g., "My mind wandered") and 3 comparison domains, mechanics (e.g., "The car is dead"), nature (e.g., "The wind is howling"), and emotion (e.g., "Her heart was smiling"). In an explanation task, we asked children to explain the processes underlying the making of both instant photos and mental images. The findings reveal a developing ability to interpret and produce statements personifying the mind and provide considerable evidence about children's movement toward a conception of the mind as an independent entity deserving reference and conceptualization in its own right.  相似文献   
880.
In this work, synchronization of chaotic Colpitts circuits, using adaptive controllers to combat circuit parameter mismatches and channel distortions, is studied by numerical simulations. Synchronization errors caused by different main circuit components are compared, and compensation for time-constant and time-varying circuit parameter mismatches is demonstrated. Different kinds of channel distortions, including time-constant and time-varying channel attenuation, Additive White Gaussian Noise (AWGN) are all investigated by numerical simulations and discussed. Simulation results indicated that the synchronization performance of chaotic Colpitts circuits can be greatly improved by applying adaptive controllers when parameter mismatches and channel attenuation are considered as time-constant or time-varying, but have no obvious enhancements regarding the effect on AWGN channel.  相似文献   
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