Modelling students' construction of energy models in physics

One of the main differences between novice and expert problem solving in physics is that novices mostly construct problem representations from objects and events in the experimental situation, whereas experts construct representations closer to theoretical terms and entities. A main difficulty in physics is in interrelating these two levels, i.e. in modelling. Relatively little research has been done on this problem, most work in AI, psychology and physics education having concentrated on how students use representations in problem solving, rather than on the complex process of how they construct them. We present a study that aims to explore how students construct models for energy storage, transformation and transfers in simple experimental situations involving electricity and mechanics. The study involved detailed analysis of problem solving dialogues produced by pairs of students, and AI modelling of these processes. We present successively more refined models that are capable of generating ideal solutions, solutions for individual students for a single task, then models for individuals across different tasks. The students' construction of energy models can be modelled in terms of the simplest process of modelling — establishing term to term relations between elements of the object/event world and the theory/model world, with underlying linear causal reasoning. Nevertheless, our model is unable to take into account more sophisticated modelling processes in students. In conclusion we therefore describe future work on the development of a new model that could take such processes into account.1. CHENE = CHaîne ENErgetique, or Energy Chain. (In French Chêne also means oak).2. Throughout the rest of the paper we use the following simple notation in order to avoid possible confusion between modelling as a process performed by the students, in the domain of physics, and AI modelling of the former modelling process: students' modelling in physics = modelling _SP ; AI modelling (of modelling _SP ) = modelling _AI .3. It has not been necessary to use more sophisticated strategies at the stage of our work reported here. The next system, modelCHENE, will directly address this issue.4. Note that what we refer to in this context as problem solving may in another context be viewed as construction of a qualitative representation for subsequent quantitative problem solving.5. The protocols indicate that students use this as a kind of anchor in their reasoning-some students returning to it in order to resolve impasses. As the current problem solver provides no mechanism for handling impasses we cannot model the reuse of information in any meaningful way.6. We are grateful to an anonymous reviewer for this example.7. This provides the minimum distinction for our initial needs.8. Though there is a difficult step in deciding that the moving object really is the last unassigned object-since that requires setting aside any need to assign roles to, for example, connecting strings etc.9. At the moment we have to provide psCHENE with slightly different rulesets: providing rules with priorities would be more convenient.     

Teachers' and prospective teachers' explanations of liquid‐state phenomena: A comparative study involving three European countries

As contact with liquids occurs from an early stage in individuals' lives, children construct explanations for liquids and liquid‐state phenomena. These may differ from the accepted scientific explanations, interfere with formal teaching, and even persist until entry into higher education. The objective of this investigation is to compare student‐teachers' and in‐service science teachers' explanations for liquid‐state phenomena, in three European countries. Data were collected by means of a questionnaire applied to 195 Italian, Portuguese, and Spanish in‐service science teachers. Data analysis revealed poor performance among participants, showing low percentages of correct answers. In addition, no systematic differences were found between participants from the three countries, and teaching experience seems to minimize some of the conceptual difficulties showed by in‐service teachers. Globally, science education seems to have had a limited effect on student‐teachers' and in‐service science teachers' conceptions. We conclude that more attention should be paid to the liquid state in both initial and continuing teacher education programs so that teachers can understand more clearly liquid‐state phenomena and succeed in explaining them to their students. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 349–374, 2007     

The underachievement of girls in physics: Towards explanations

The recently initiated debate on the relationship between science and health education is discussed. The notions of ‘everyday’, ‘scientific’ and ‘applied’ knowledge are explored through interview material gathered from a sample of 15‐year old pupils. The topic of the interviews was the common cold. The pupils’ levels of biological knowledge, their mode of applying it, and the frameworks of their thinking about infection and related issues were investigated. It is argued that no simple ‘translation’ of scientific to health knowledge is possible. Some of the complexities of the relationship are explored. In particular, the implications of non‐scientific ('lay’ or ‘traditional') knowledge are taken up and it is suggested that scientific knowledge may face considerable obstacles in displacing these.

     

Self-generated analogies as a tool for constructing and evaluating explanations of scientific phenomena

How can students be taught to develop explanations for scientific phenomena on their own when their background knowledge is incomplete or poorly organized? Evidence from historical accounts of scientific discovery suggest that self-generated analogies—analogies produced by the learners themselves—are a tool by which individuals can generate, evaluate, and modify their own explanations. The central research questions for this study were: Can students use a series of self-generated analogies to bring about change in their understanding of a given scientific phenomenon, and what is the nature of the change in understanding? Participants were asked to create, apply, and modify their own analogies—as opposed to applying a specific analogy provided by an outsider—as a heuristic for constructing, evaluating, and modifying their own explanations for a given scientific phenomena. Nontrivial changes in explanation facilitated by the use of generative analogies were observed. Changes in understanding ranged from the emergence of new explanations to the raising of important questions about the nature of the phenomenon.     

Professors' and students' conceptualizations of the learning task in introductory physics courses

What are students expected to learn in physics courses? Eight expert physics teachers and researchers, two from the University of Western Ontario in Canada, Cambridge University in the United Kingdom, Stanford University in the United States of America, and Monash University in Australia, described their perceptions of learning in their courses. Students from the courses were then interviewed for their perceptions of learning in physics courses. In their courses, professors focused on the development of intellectual skills, assuming that students had a specific physics vocabulary. Students, however, were aware of their own limitations and suggested that professors should take nothing for granted. Students considered that to be a good teacher, a professor should know the perspective of the students and should start at the students' level. The results suggested that the intellectual challenge of learning physics merits early explanation.     

Impact of model-based science curriculum and instruction on elementary students' explanations for the hydrosphere

Developing scientific literacy about water systems is critical for K-12 students. However, even with opportunities to build knowledge about the hydrosphere in elementary classrooms, early learners may struggle to understand the water cycle (Forbes et al., 2015 ; Gunckel et al., 2012 ; Zangori et al., 2015 ; Zangori et al., 2017 ). Scientific modeling affords opportunities for students to develop representations, make their ideas visible, and generate model-based explanations for complex natural systems like the water cycle. This study describes a comprehensive evaluation of a 5-year, design-based research project focused on the development, implementation, revision, and testing of an enhanced, model-centered version of the Full Option Science System (FOSS) Water (2005) unit in third grade classrooms. Here, we build upon our previous work (Forbes et al., 2015 a; b; Vo et al., 2015 ; Zangori et al., 2015 ; Zangori et al., 2017 ) by conducting a comparative analysis of student outcomes in two sets of classrooms: (1) one implementing the modeling-enhanced version of the FOSS Water unit developed by the research team (n = 6), and 2) another using the standard, unmodified version of the same curricular unit (n = 5). Results demonstrate that teachers in both conditions implemented the two versions of the curriculum with relative fidelity. On average, students exposed to the modeling-enhanced version of the curriculum showed greater gains in their model-based explanations for the hydrosphere. Engagement in scientific modeling allowed students to articulate hydrologic phenomena by (1) identifying various elements that constitute the hydrosphere, (2) describing how these elements influenced the movement of water in the hydrosphere, and (3) demonstrating underlying processes that govern the movement of water in the hydrosphere.     

A causal model of students' achievement in a college physics course

To explain students' achievement in the mechanics segment of a college physics course, a causal model is proposed whose variables are the three constructs: Newtonian physics, math ability, and science experience. Each variable specifies several variates, whose numerical values were measured and intercorrelations computed. The Factorial Modeling (FaM) procedure is applied to the data to estimate the coefficients of the proposed model's structural equations. The FaM results indicate that the model is plausible and that its first two variables account for approximately 34% of the variance in the criterion variate, students' mechanics achievement. The implications of the findings for physics instruction are discussed.     

Causal modeling of secondary science students' intentions to enroll in physics

The purpose of this study was to explore the utility of the theory of planned behavior model developed by social psychologists for understanding and predicting the behavioral intentions of secondary science students regarding enrolling in physics. In particular, the study used a three-stage causal model to investigate the links from external variables to behavioral, normative, and control beliefs; from beliefs to attitudes, subjective norm, and perceived behavioral control; and from attitudes, subjective norm, and perceived behavioral control to behavioral intentions. The causal modeling method was employed to verify the underlying causes of secondary science students' interest in enrolling physics as predicted in the theory of planned behavior. Data were collected from secondary science students (N = 264) residing in a central Texas city who were enrolled in earth science (8th grade), biology (9th grade), physical science (10th grade), or chemistry (11th grade) courses. Cause-and-effect relationships were analyzed using path analysis to test the direct effects of model variables specified in the theory of planned behavior. Results of this study indicated that students' intention to enroll in a high school physics course was determined by their attitude toward enrollment and their degree of perceived behavioral control. Attitude, subjective norm, and perceived behavioral control were, in turn, formed as a result of specific beliefs that students held about enrolling in physics. Grade level and career goals were found to be instrumental in shaping students' attitude. Immediate family members were identified as major referents in the social support system for enrolling in physics. Course and extracurricular conflicts and the fear of failure were shown to be the primary beliefs obstructing students' perception of control over physics enrollment. Specific recommendations are offered to researchers and practitioners for strengthening secondary school students' intentions to study physics.     

先进接插件在物理电磁学实验中的应用研究

以先进接插件在磁性材料基本特性的研究实验中的应用为例,从实验方法选择、仪器设备选用、电路设计等方面总结了应用先进接插件开设组合式实验的实践体会,实现了学生自搭实验仪器,并用自搭实验仪器进行测量的目的.这不仅锻炼了学生的动手能力,丰富了实验的内容,开阔学生的视野,培养学生把多种物理知识交叉使用来解决实际问题的能力;同时也打破了仪器由厂家设计、用户无法改变的模式,使实验设备具备了综合化、模块化、透明化.     

中职物理教学与学生数学基础相衔接的应对策略

扎实的数学基础是学生学好中职物理的前提.找准中职物理与学生数学基础知识的衔接点,并采取相应的策略,使学生尽快地适应中职阶段物理学习,从而更好地理解中职阶段的物理知识和提高学习物理的能力.     

Testing one premise of scientific inquiry in science classrooms: Examining students' scientific explanations and student learning

In this study, we analyzed the quality of students' written scientific explanations found in notebooks and explored the link between the quality of the explanations and students' learning. We propose an approach to systematically analyzing and scoring the quality of students' explanations based on three components: claim, evidence to support it, and a reasoning that justifies the link between the claim and the evidence. We collected students' science notebooks from eight science inquiry‐based middle‐school classrooms in five states. All classrooms implemented the same scientific‐inquiry based curriculum. The study focuses on one of the implemented investigations and the students' explanations that resulted from it. Nine students' notebooks were selected within each classroom. Therefore, a total of 72 students' notebooks were analyzed and scored using the proposed approach. Quality of students' explanations was linked with students' performance in different types of assessments administered as the end‐of‐unit test: multiple‐choice test, predict‐observe‐explain, performance assessment, and a short open‐ended question. Results indicated that: (a) Students' written explanations can be reliably scored with the proposed approach. (b) Constructing explanations were not widely implemented in the classrooms studied despite its significance in the context of inquiry‐based science instruction. (c) Overall, a low percentage of students (18%) provided explanations with the three expected components. The majority of the sample (40%) provided only claims without any supporting data or reasoning. And (d) the magnitude of the correlations between students' quality of explanations and their performance, were all positive but varied in magnitude according to the type of assessment. We concluded that engaging students in the construction of high quality explanations may be related to higher levels of student performance. The opportunities to construct explanations in science‐inquiry based classrooms, however, seem to be limited. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 47: 583–608, 2010     

浅谈MATLAB在物理教学中的应用

本文根据物理教学的特点,简单介绍了MATLAB的特点和功能.通过对物理教学中电力线、等高线等实例分析,提出了使用MATLAB图形处理的优势及教师在教学中的可操作性.     

Social interaction and the use of analogy: An analysis of preservice teachers' talk during physics inquiry lessons

Analogies have been argued to be central in the process of establishing conceptual growth, making overt connections and carryover into an intended cognitive domain, and providing a generative venue for developing conceptual understanding inherent in constructivist learning. However, students' specific uses of analogies for constructing arguments are not well understood. Specifically, the results of preservice teachers' knowledge gains are not widely studied. Although we would hope that engaging preservice science teachers in exemplary lessons would assist them in using and generating analogies more expertly, it is not clear whether or how such curricula would affect their learning or teaching. This study presents an existence proof of how preservice science teachers used analogies embedded in their course materials Physics by Inquiry. This fine‐grained analysis of small group discourse revealed three distinct roles of analogies including the development of: (a) cognitive process skills, (b) scientific conceptual understanding, and (c) social contexts for problem solving. Results suggest that preservice teachers tend to overgeneralize the analogies inserted by curriculum materials, map irrelevant features of analogies into collaborative problem solving, and generate personal analogies, which counter scientific concept development. Although the authors agree with the importance of collaborative problem solving and the insertion of analogies for preservice teachers' conceptual development, we believe much more needs to be understood before teachers can be expected to construct and sustain effective learning environments that rely on using analogies expertly. Implications for teacher preparation are also discussed. © 2003 Wiley Periodicals, Inc. J Res Sci Teach 40: 443–463, 2003     

利用大学物理实验平台培养学生实践创新能力

以成都大学部分理工科专业学生的实践创新能力发展为例,结合大学物理实验的现状,分析抑制本科生创新意识和创新能力的形成因素,提出如何利用大学物理实验平台激发大学生的创新思维,推广研究性学习和个性化培养的创新教学方式,对培养学生实践创新能力,具有一定的战略意义和现实可行性。     

Instability in students' use of intuitive and Newtonian models to predict motion: the critical effect of the parameters involved

This study reports how children switch from intuitive to scientific models of explanation of motion when the numerical conditions in the presented problem are changed. Previous studies have suggested that student knowledge of mechanics may be compartmentalized: their everyday intuition serves in everyday contexts and their scientific model is activated, if ever, in academic contexts. In this study we investigate a case where significant numbers of students appear to draw on different models of motion in what is essentially the same, academic context, i.e. the prediction of the motion of a block on a smooth surface under the action of horizontal forces. Many students exhibit combinations of Aristotelian-like intuitions and Newtonian conceptions depending on the magnitudes of the quantities involved. The students' experience of being taught Newtonian theory in mathematics and physics has small but significant effects on the explanations they offer. The notion of anchoring and bridging is re-examined as a teaching strategy in such situtions.     

对"大、中学物理教学方法相互衔接"的研究

分析了大、中学物理教学方法衔接的现状，总结出大、中学物理教学方法顺利衔接的措施。     

填补法在物理教学中的应用

本文介绍一种在物理教学中,把非对称问题转化为对称问题进行求解的方法。这种方法思路清晰、数学演算简单,方便求解。     

Intuitive ideas and scientific explanations as parts of students' developing understanding of biology: The case of evolution

Questions concerning 13–16 year old students' developing understanding of different biological concepts related to the theory of evolution of species are focused. The aim is to get more detailed examples of the ways in which students understand complex biological concepts and the development of these concepts. Data were collected from two different periods: at the beginning of the seventh and at the end of the ninth grade of the Swedish compulsory school. The examples given show how students, in various ways, construct and develop their understanding of animal and plant adaptation to nature, with the help of their biological knowledge as well as by alternative and more intuitive ideas about the function of nature. The varying abilities of students to express their ideas are discussed as well as different arguments concerning the student's difficulties in adapting to scientific ideas from more intuitive ideas.