Using multimedia to overcome the problems with problem based learning

Much of the literature on problem based learning (PBL) is concerned with efficacy or with guidelines on design or implementation. Relatively few articles focus on problems with problem based learning, and none that we could find provided suggestions as to how interactive multimedia might help alleviate those problems. In this article we begin with a review of problem based learning including a rationale for its use in the curriculum. Then we identify some of the problems inherent in designing and implementing problem based learning, and end the article with a discussion of how multimedia might be used to address some of those problems.     

Using an analogy to model causal mechanisms in a complex text

Two experiments examined the role of analogy inthe development of a situation model of atarget passage. Specifically, we examinedwhether an analogous source text could improvecomprehension and inferencing about causalmechanisms in the target. An ``analogy group'studied a fictional pseudo-scientific passageunder the guidance of an analogous passage(also fictional) which shared causal structureswith the target. A ``statement group' studiedthe target under the guidance of an abstractstatement that characterized the target causalstructures. A ``target-only group' received noadditional material. All groups received tasksthat assessed their representation of thetarget. In Experiment 1 (N = 92) participantswere asked to list the most important objectsand relations in the passage. In Experiment 2(N = 80) participants were directly asked aboutthe target causal structures. In bothexperiments, responses of analogy subjects weremore likely to include given and inferredinformation that comprised the target causalmechanisms. Analogies in which a sourcepassage models causal mechanisms correspondingto those of a target passage appear to promotebetter representation of the details of targetcausal mechanisms, allowing a more fullydeveloped situation model of the target.     

Students' misconceptions about U.S. westward migration

Fifth-grade students with learning disabilities (LD) and their typically achieving (TA) peers participated in an 8-week investigation about 19th-century U.S. westward migration. During their investigations, the students analyzed primary and secondary sources to understand the experiences of these emigrants and Native peoples. The analysis of source material was preceded by teacher-led discussions about the possibility of bias in evidence that affects the trustworthiness of historical documentation. Quantitative analyses showed that these investigations were associated with gains in students' knowledge about the period of westward expansion and a better understanding of historical content and historical inquiry; however, these gains were not always comparable for students with LD and their TA peers. Furthermore, misconceptions about this historical period and the processes of historical investigation were evident in students' responses before and after instruction. We discuss how design features of the instruction and its implementation may have contributed to the development and persistence of these misconceptions.     

对“类平抛运动”的一些探讨和再认识

根据平抛运动的定义,把与平抛运动相类似的一些运动定义为一种＂新＂的运动——类平抛运动,通过研究类平抛与平抛运动在哪些方面是相类似的,常见的哪些运动可被看成是类平抛运动,我们将能更深刻、全面地认识类平抛运动和其他一些运动。     

Learning about forces: simulating the outcomes of pupils' misconceptions

We have developed a computer program which simulates the outcomes of pupils' perceptions regarding the forces at play in static equilibrium. A pupil is presented with a simulation of his or her own private microworld which may or may not be compatible with familiar behaviour in the real world. The program includes a tutor which helps the pupil learn the relevant scientific concepts if he or she cannot solve the problem without help.This dissonance-based strategy for achieving conceptual change was made possible by the use of a language which enables pupils to express their conceptual understanding. To date, researchers have relied primarily on natural language interfaces with all the difficulties inherent in such an approach; we chose to use a simple vector language appropriate to the study of forces. This language accurately quantifies pupils' understanding and allows the designer to create highly reactive and seemingly intelligent programs.     

Using an analogy in the introduction of a portfolio

Students in many teacher education programmes experience confusion about portfolios. This study investigated whether using an analogy in the introduction of a portfolio helps teacher education students understand both the purpose of a portfolio and how to compile it. It was also investigated whether these students’ understanding correlates with their appreciation of portfolios. In the analogy, portfolios were compared with job application letters, curricula vitae and the references that are common in selection procedures for new employees. This analogy was helpful in promoting students’ understanding. Their understanding correlated with their appreciation of this instrument.     

Misconceptions in Van den Broeck's representation of misconceptions about learning disability research

The methods and conclusions of Van den Broeck (in this issue) are evaluated from two perspectives: (a) statistical considerations and (b) theoretical models of IQ and achievement, specifically reading achievement. We consider the statistical model proposed by Van den Broeck for the regression-based discrepancy model (RDM) to be either irrelevant or conceptually inconsistent with current models of IQ and achievement. The resulting simulation produced exemplar cases that are not realistic in terms of practice. The theoretical representations of IQ and achievement were, in our understanding, inconsistent with contemporary models of either. We suggest that acceptable models support the use of the RDM as it has been proposed by us and by others as one component of the determination of the presence or absence of a learning disability.     

对机械能守恒条件的讨论

本文用牛顿力学方法分析了机械能守恒的条件,指出只有力满足旋度(?)×(?)=0的条件,而且在势能的表达式中不显含时间,机械能才守恒．     

国有教育培训机构走出困境的思考

近几年，随着培训市场竞争的日渐激烈。一些国有教育培训机构的培训工作逐渐进入了困难时期：一方面我国的培训市场越来越大，培训的种类越来越多；另一方面国有教育培训机构的培训规模越来越小，培训项目的开发越来越难。造成这种状况的根本原因是思想观念、组织机构、人员素质和工作机制还不适应市场经济和对外开放的需要。因此，要使培训工作走出困境，再创辉煌，必须在实际工作中做到“四个坚持”。[编按]     

巧用肢体语言,突破教学难点——谈染色体变异一节的难点突破

运用抽象问题形象化的教学策略,充分挖掘肢体语言的特点,运用肢体语言解决教学中出现的难点,使学生在学习的过程中体会到学习的乐趣。     

也谈"暗物质"

1"暗物质"是当今世界四个最大科学难题之一.其它三大难题分别是:人体基因结构、受控核聚变以及生命的起源.其研究基本情况是: 1.人体基因结构:人的基因存在于一个螺旋形大小的分子中,科学家希望能准确地知道在哪一种基因中存储哪些信息,因为每种基因由约3万个信息构成,要一个一个地检查.现在才查明约10万种基因中的100种.目前,科学家们已解出一个志愿者的全部基因密码,如能揭开全部基因的秘密,那么由于基因受损而引起的癌症、糖尿病以及4000多种遗传疾病都可以通过修复基因来根治.     

图解法突破教学难点例举

分析说明：光合作用和呼吸作用是教学的重点,也是教学的难点。特别是关于光合作用和呼吸作用的混合计算,学生颇感棘手。这是因为在计算的过程中学生常常把“光合作用总量”与“净光合作用量”、“氧气释放量”与“氧气产生量”、“有机物合成量”与“有机物积累量”等相关联的概念混为一谈。为了解决这一难点,采取直观图示的方法,辨别易混淆的概念,这是关键。步骤如下：①先绘制右图。②分三种情况,让学生进行讨论。这三种情况分别是：黑暗条件下,不进行光合作用,但进行呼吸作用;弱光条件下,光合作用强度小于呼吸作用强度;强光条件下,光合作用强度大于呼吸作用强度。在各自条件下,     

略谈克服舞蹈表演紧张心理的有效方法

克服恐惧感对于舞蹈演员来说是一个非常值得关注的问题。本文从紧张感产生的原因出发,通过分析,建议采用脱敏练习法、自律训练法和练习过程自动化的方式来消除舞蹈演员在舞台上的紧张感与恐惧感。     

RAROC绩效考核运用研究

长期以来,我国商业银行衡量盈利能力指标普遍采用ROA和ROE,没有将风险考虑在内,这在一定程度上导致了商业银行的非理性扩张。风险调整后的资本收益率(RAROC)指标,不仅实现了业务发展与风险控制的内在统一,而且可以指导经济资本配置。我国商业银行运用RAROC进行产品考核并指导资本配置,需要建立经济资本管理体系,细化成本核算并合理确定内部资金转移价格。     

Using a computer game to teach school-aged children about asthma

The purpose of this study was to determine whether playing Quest for the Code?, a computer game designed to teach children about asthma, would help healthy children acquire knowledge about and attitudes towards asthma and whether the beneficial effects would be maintained over time. The sample consisted of 155 children from four middle schools who were randomly assigned to play Quest for the Code? or a game about nutrition serving as the control condition. Data were collected on knowledge and attitude pre-intervention, post-intervention, and at follow-up four weeks later. The results revealed that children who played Quest for the Code? were more knowledgeable and had more positive attitudes than their peers in the control condition. And these benefits were maintained on follow-up tests. Our findings indicate the effectiveness and potential of using Quest for the Code? as a tool for asthma education in a classroom setting.