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951.
The purpose of this study was to describe and understand the range of outcomes of class visits to natural history museums. The theoretical framework is based on the multifaceted process of learning in free choice learning environments, and emphasizes the unique and individual learning experience in museum settings. The study’s significance is in highlighting several possible cognitive as well as non-cognitive learning effects in museums class visits, by providing the student’s point of view. Data was collected by semi-structured interviews with 50 students in grades 6–8 on the day following the visit. We present evidence that students expressed several learning outcomes, connected directly and indirectly to the scientific content of the visit. Content oriented outcomes included acquiring scientific knowledge and making connections to prior knowledge; social oriented outcomes were identified in students’ statements regarding communicating knowledge and social aspects of learning; and interest oriented outcomes were evidenced by students’ expressions about emotions, interest and curiosity. The aggregate data addressed the common outcomes and the impact of class visits to natural history museums in the short term. Comparisons between two types of museums show significant differences in several aspects, regarding the exhibit and/or the activity type. Practical ideas for structuring the ultimate experience are included.  相似文献   
952.
One of the great strengths of Jim Kaput’s research program was his relentless drive towards scaling up his innovative approach to teaching the mathematics of change and variation. The SimCalc mission, “democratizing access to the mathematics of change,” was enacted by deliberate efforts to reach an increasing number of teachers and students each year. Further, Kaput asked: What can we learn from research at the next level of scale (e.g., beyond a few classrooms at a time) that we cannot learn from other sources? In this article, we develop an argument that scaling up research can contribute important new knowledge by focusing researchers’ attention on the robustness of an innovation when used by varied students, teachers, classrooms, schools, and regions. The concept of robustness requires additional discipline both in the design process and in the conduct of valid research. By examining a progression of three studies in the Scaling Up SimCalc program, we articulate how scaling up research can contribute to designing for and evaluating robustness.  相似文献   
953.
McNeil NM 《Child development》2008,79(5):1524-1537
Do typical arithmetic problems hinder learning of mathematical equivalence? Second and third graders (7–9 years old; N= 80) received lessons on mathematical equivalence either with or without typical arithmetic problems (e.g., 15 + 13 = 28 vs. 28 = 28, respectively). Children then solved math equivalence problems (e.g., 3 + 9 + 5 = 6 + __), switched lesson conditions, and solved math equivalence problems again. Correct solutions were less common following instruction with typical arithmetic problems. In a supplemental experiment, fifth graders (10–11 years old; N= 19) gave fewer correct solutions after a brief intervention on mathematical equivalence that included typical arithmetic problems. Results suggest that learning is hindered when lessons activate inappropriate existing knowledge.  相似文献   
954.
There are many influences on how assessors grade themselves and others. Oral presentations are useful for exploring such factors in peer, self‐ and tutor marked assessments, being rapidly completed and assessed, commonly used in HE and very difficult to anonymize. This opportunistic study examined the effects of gender and level of attainment on the triangulation of marks awarded to student presenters. Grades generated by peer assessment were associated more strongly with tutor‐awarded marks than those from self‐assessment. For self‐assessment there was a strong effect of gender (female students undervalued their performance compared with tutor grades). Peer assessment produced higher marks than from tutors, perhaps because of the close‐knit community developed during residential courses. For tutor marks, the greatest variability was at the lower end of the scale, whereas peer assessors were most variable when marking students who self‐evaluated or peer assessed highly. Students awarded a narrower range of marks to peers compared with tutors, but when self‐assessing used a larger range. Presentations by students who admitted to little sleep the night before received lower grades from both peers and tutors, but this was not reflected by self‐assessments, suggesting they were unaware of their poorer performances. Sessions with fewer talks (four rather than seven) reduced the ‘dip’ in marks previously observed in the middle of sessions. Findings are discussed in the context of bias in this mode of assessment.  相似文献   
955.
This paper presents a novel mega-Hz-level super high frequency zero-voltage soft-switching converter for induction heating power supplies. The prominent advantage of this topology is that it can absorb both inductive and capacitive parasitic components in the converter. The switch devices operate in a zero-voltage soft-switching mode. Consequently, the high voltage and high current spikes caused by parasitic inductors or capacitors oscillation do not occur in this circuit, and the high power loss caused by high frequency switching can be greatly reduced. A large value inductor is adopted between the input capacitor and the switches, thus, this novel converter shares the benefits of both voltage-type and current-type circuits simultaneously, and there are no needs of dead time between two switches. The working principles in different modes are introduced. Results of simulation and experiments operated at around 1 MHz frequency verify the validity of parasitic components absorption and show that this convener is competent for super high frequency applications.  相似文献   
956.
This paper studies the social talk of high school students in online discussion forums. On-task talk has generally been assessed as valuable discussion because it contributes directly to productive learning. Off-task conversation, on the other hand, is often regarded as useless and a waste of time. Should this social talk indeed be regarded as an off-task activity? Is social talk such as greeting, excusing, comforting and sharing personal feelings irrelevant to learning? This study analyzes threads and argues that social talk is interwoven with on-task talk. It is interesting to note that a substantial quantity of off-task messages served the latent function of guiding group discussion toward making progress in solving collaborative problems in a subtle and indirect manner. The power of “soft talk” embedded in off-task social conversation is explored and fully discussed.  相似文献   
957.
In Iran, restructuring of medical education and the health care delivery system in 1985 resulted in a rapid shift from elite to mass education, ultimately leading to an increase in the number of medical schools, faculties, and programs and as well as some complications. This study aimed to investigate views on academic culture, values, and routines held by faculty members. A nation-wide survey conducted in six public medical schools in Iran. The research findings show weak organizational culture and values, together with routine behaviors sensed as a negative and low satisfaction with academic leadership. The research evidence suggests bureaucracy, politicization, conservativeness, and centralization as common features of medical schools in Iran and also suggests suitable supervisory skills to tackle the tension between governmental management and academic leadership with cultural changes, the creation of new values, and adoption more efficient routines.  相似文献   
958.
Interdisciplinary work within higher education has increased significantly over past decades (Amey 2004; Creamer and Lattuca 2005). However, the professional implications of interdisciplinary research and instruction for the faculty members who engage in such academic work remain unclear. This study of science educators who hold appointments in two academic departments begins to address this empirical gap. The outcomes provide insight into the factors that influence the professional lives of these faculty members. The knowledge gained from the study will provide mentors, colleagues, and administrators insight into the challenges facing academics undertaking this work. Further, this research seeks to inform policy makers in regard to how tenure and promotion is determined for jointly appointed faculty in science education and other interdisciplinary fields.
Matthew M. MarsEmail:
  相似文献   
959.
This case study describes the efforts of librarians to integrate mobile devices, collaboration tools, and resources into a School of Medicine third-year pediatric clerkship. Additional class emphasis is on evidence-based searching and journal article evaluation and presentation. The class objectives ensure that students are comfortable with mobile devices and collaboration tools. Over the eight-year history of the course, student acceptance of the mobile devices used diminished as the devices aged, necessitating the evaluation and selection of new technologies. Collaboration tools and mobile applications employed in the course evolved to accommodate curriculum changes.  相似文献   
960.
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