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991.
The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:
- 1 How is the mole defined?
- 2 What concepts about the atom are introduced prior to the mole?
- 3 Is Avogadro's constant presented as an experimentally determined value?
- 4 What is the context for introducing the mole?
- 1 Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12.
- 2 All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole.
- 3 Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity.
- 4 Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy.
992.
Cognitive theory suggests that a key to expert performance lies in the internal organization of the expert's knowledge. The authors contend that the type of technical illustration used during instruction influences knowledge organization and greatly impacts students' understanding of the content. This paper describes an experimental study that tested the impact of one type of conceptual illustration on students' understanding of the structure, function, and behavior of complex technical systems. The results show that supplementing traditional technical instruction with functional flow diagrams can improve overall system understanding. The functional flow diagrams were also found to be an effective instructional aid for enhancing students' conceptual understanding of the causal behavior of systems. In addition, the use of the functional flow diagram was found to significantly improve the subjects' ability to construct conceptual models that were similar to those of an expert. The implications of using conceptual diagrams for technical instruction are discussed and recommendations for future research in this area are provided. 相似文献
993.
Judith A. Sutter Edward J. McCaul 《International journal for the advancement of counseling》1993,16(1):3-18
While there is a clear need to address the ethical dimensions of cross-cultural counseling, the current literature lacks both a theoretical model of ethnic tolerance and a suitable measure for assessing the construct. The present study addressed this gap in the extant literature by (a) developing a measure of ethnic tolerance based upon extensive field work, (b) examining the measure's reliability and construct validity in light of two models of ethnic tolerance, and (c) examining the relationship of several factors (e.g., age, gender, and exposure to those of a different culture) to scores on the tolerance measure. Results indicated that the tolerance measure was best viewed as a unidimensional construct, had substantial content validity, and had modest construct validity. Respondents with more social contact with immigrants, as well as those who had positive experiences with immigrants, tended to score higher on the tolerance measure. Results underscore both the complexity of factors associated with tolerance and the need for counselor education programs to provide arenas for students to become aware of their own values and biases and how these may affect culturally-different clients. 相似文献
994.
Mary Jane Feldman Ph.D. 《Research in higher education》1993,34(4):503-512
This study sought to evaluate preenrollment variables as predictors of one-year retention of first-time students in a community college. The purpose was to use information that is typically available when a student begins his or her college program and determine if this information can help identify students who are more likely to drop out within their first year. Based on a logistic regression model to select predictors of retention, the lower the high school GPA, the greater the chance the student will drop out. Over and above this, additional risk is associated with the age range 20–24, attending part-time, and being an ethnic minority other than Asian. When all or some of these are operating, it may be necessary to enhance these students' chances with special programs or services. 相似文献
995.
It would seem a foregone conclusion that early childhood program directors need a knowledge base in child development if they are to establish credibility in their role as directors (Kuykendall, 1990). The general assumption, then, is that directors' client base is young children. However, early childhood program directors in their daily experiences deal with opposite ends of the development continuum from children to adults.Sharon L. Wooden is Professor, Department of Curriculum and Instruction, New Mexico State University, Las Cruces, NM. Nancy E. Baptiste is Coordinator, Child Development Associate Program, New Mexico State University, Las Cruces. 相似文献
996.
This paper addresses the question of the extent to which there were improvements in equity in the patterns of participation of young people in higher education in Australia during the 1980s. Data from theYouth in Transition longitudinal surveys of Australian youth are used to assess the effectiveness of the Labor Government's equity initiatives since 1983 in this area. The conclusion is that participation by young people in higher education in Australia did generally become more equitable under Labor during the 1980s, though differences in higher education participation rates persisted between certain sub-groups of the population. 相似文献
997.
In order to determine how well medical examiners agree on the significance of certain anogenital findings in children, preselected colposcopic photographs of the anogenital area of 16 patients were shown to 170 medical examiners (82% pediatricians) who were blinded as to the history on each patient. Findings rated most frequently as being suggestive or indicative of penetrating injury included immediate anal dilatation with no stool present (85%), hymenal transection (84%), marked narrowing of the hymenal rim with notching (81%), and a posterior fourchette scar (75%). The agreement between the participants and the experts on the abnormal cases (mean 81%) was significantly higher than on the normal cases (mean 71%, p < .001) and on genital findings (78%) than on anal findings (63%, p = .000). Higher experience level (more cases seen per month) was associated with significantly higher agreement between the participants and the experts on five of eight normal cases and two of four abnormal cases. Use of a colposcope was also associated with higher overall agreement with the experts (74% vs. 44%, p < .0001). 相似文献
998.
The six national goals established by the National Governors' Association for education reform in the 1990s were conceived by people who had the power to decide what outcomes they wanted based on their own values and priorities. Although it is impossible to avoid questions of values, it is necessary in defining goals for education to consider scientific, explanatory theories about how human beings acquire knowledge and moral values. Jean Piaget's conceptualization of autonomy, in his unusual sense of the term, provides an overall aim for the development of individuals as well as of society, both in the intellectual and the moral realms. Autonomy as the aim of education is based on constructivism, a scientific theory, and would obviate the outdated conceptualization and contradictions among the six national goals. 相似文献
999.
Through this study the authors evaluate outcomes associated with the use of handheld computers by interventionists in improving the efficiency of direct systematic classroom observation. Information from observations is used by interventionists for treatment planning and evaluation. In this study, interventionists were trained to use personal digital assistants with classroom observational software for use with students who displayed low levels of academic engagement. Results indicated that the personal digital assistants and observational software were perceived as user-friendly, increased computer self-efficacy, and facilitated treatment planning and evaluation. Discussion focuses on implications for use of handheld computers and mobile devices by interventionists. 相似文献
1000.
Susan T. Dennison Kenneth J. Gruber Lucas Vrbsky 《Journal of Teaching in Social Work》2013,33(4):399-419
This article presents a review of research studies examining instructional methods reported in the social work education literature published between 1998 and 2008. From a sample of 91 studies, 31 were identified as having used either a single group pre/post test design or a comparison of two or more groups and inclusion of a learning outcome measure. Most of the studies were deficient in either the employment of comparison groups, pre/post designs, utilization of multiple learning outcome measures, or a clear delineation of the connection between teaching methods and learning outcomes. Very few studies were based on previous work. A challenge is made to the field to conduct better designed studies and several suggestions for doing so are offered. 相似文献