Concept substitution: An instructional strategy for promoting conceptual change

Numerous studies have shown that students often hold conceptions that conflict with accepted scientific ideas, both prior to and after instruction. The failure of instruction to affect students' conceptions can be interpreted as a failure to facilitate conceptual change. In this paper, an instructional strategy will be described that facilitates conceptual change in the special case where conceptual difficulties appear to arise because students confuse related physics concepts. The strategy involves two parts. Firstly, students observe an experiment or demonstration that conflicts with what they expect to see. Secondly, the instructor identifies students' intuitions that are correct but that they have associated with an incorrect physics term, and substitutes the correct physics term. Students can thus develop more scientifically acceptable understandings of physics concepts without having to give up their intuitive ideas. The use of this strategy will be illustrated in two domains of physics. Specializations: physics education, conceptual development, instructional design, improvement of tertiary science education.     

素质教育呼唤灵动的物理课堂

本文针对目前物理教学受应试教育的影响扼杀学生的个性和创造性的弊端 ,提出了灵动的物理课堂应当让学生成为学生的主人。发挥学生的主动性和创造性。培养学生的创造性学习能力 ,包括创造性学习的兴趣、动力 ;创造性思维、创造性学习实践 ,提倡活跃和活动 ,提倡质疑发问 ,鼓励奇思异想 ,摒弃死记硬背 ,引导学生创造性地“学”物理     

The Use of Video Demonstrations and Particulate Animation in General Chemistry

Different visualization techniques have been used for teaching chemistry concepts. Previous studies have shown that when molecular animations and video demonstrations are used, students seem to better correlate all three levels of representation: macroscopic, submicroscopic, and symbolic. This thinking process allows the students to improve their conceptual understanding and ability to create dynamic mental models. In this study, general chemistry students viewed three experiments involving dynamic fluid equilibrium in a graphic design, a video demonstration, and a molecular animation. The study investigated whether video demonstrations or particulate animations helped the students' conceptual understanding, and if the order of visualizations (video or animation first) produced any differences. Students showed improvement after each visualization. Surprisingly, there was significant improvement in responses between the first and second visualization. This work shows the importance of combining both types of visualizations, but it does not indicate a preference toward a specific order.     

Reexamining the Role of Cognitive Conflict in Science Concept Learning

In this study, we defined and quantified the degree of cognitive conflict induced by a discrepant event from a cognitive perspective. Based on the scheme developed, we investigated the relationship between cognitive conflict and conceptual change, and the influences of students' cognitive characteristics on conflict in learning the concept of density. Subjects were 171 seventh-grade girls from two city middle schools in Korea. Tests regarding logical thinking ability, field dependence/independence, and meaningful learning approach were administered. A preconception test and a test of responses to a discrepant event were also administered. Computer-assisted instruction was then provided to students as a conceptual change intervention. A conception test was administered as a posttest. In analysing students' responses to the discrepant event, seven types of responses were identified: Rejection, reinterpretation, exclusion, uncertainty, peripheral belief change, belief decrease, and belief change. These types were then ordered into four levels. The results indicated that there existed a significant correlation between cognitive conflict and conceptual change. t-test results revealed that there were statistically significant differences in the degree of cognitive conflict by the levels of students' logical thinking ability and field dependence/independence. Meaningful learning approach, however, was found to have no statistically significant effect on cognitive conflict. Educational implications are discussed.     

Using Computer Assisted Instruction to Compare the Inventive Model and the Radical Constructivist Approach to Teaching Physics

This paper introduces a new way of evaluating instructional strategies by using computers. Two basic theories, instructivism and constructivism, are discussed and critically evaluated in terms of their effectiveness in conceptual learning. Despite the current popularity of constructivism, the radical form of it is criticized in this paper. The advantages and limitations of these two approaches, especially the radical forms of constructivism, are outlined. After borrowing some ideas from other effective conceptual change models, an integrative model for conceptual learning (the Inventive Model) is introduced. Two versions of multimedia physics software are developed by the authors. The first version is based on the Inventive Model and the second version based on a radical constructivist model. The effectiveness of the Inventive Model was compared with the radical constructivist approach and conventional science instruction. Students' log files were analyzed to investigate the nature and the processes of the conceptual change. A conceptual test and a knowledge test were used to compare the groups. The quantitative results showed the superiority of the Inventive Model over the other models in conceptual learning and the superiority of conventional instruction in learning the basic knowledge. The qualitative analysis showed that only the Inventive Model lead to coherent conceptual learning. It was concluded that the process of conceptual change is gradual and continuous. Analysis of students' log files revealed no moments of dramatic change in students' conceptions.     

INTEGRATING PHYSICS AND MATH THROUGH MICROCOMPUTER-BASED LABORATORIES (MBL): EFFECTS ON DISCOURSE TYPE,QUALITY, AND MATHEMATIZATION

The purposes of this study were to understand the nature of discourse in terms of knowledge types and cognitive process, source of utterances (student or teacher), and time use in microcomputer-based labs (MBL) and verification type labs (VTL) and to gain an understanding of the role of MBL in promoting mathematization. The study was conducted in 2 grade 11 classes in which students studied Hooke’s law and Newton’s second law of motion using MBL during 1 year while a different group of students studied the same topics with the same physics teacher using a VTL approach. All sessions were videotaped, transcribed and coded using a taxonomy developed by DeVito & Grotzer (2005). In addition, evidence to support each of the 5 steps of mathematization was sought from the actions of the teachers and their discourse with the students. Results showed that conceptual knowledge type utterances were significantly more frequent in MBL sessions, cognitive processes of remembering and understanding were significantly more frequent in the MBL sessions, students spent most of their time analyzing the graphs in the MBL sessions, and MBL has a potential to promote mathematization in favorable instructional environments in physics laboratory classes.     

Enhancing Students' Understanding of Photosynthesis and Respiration in Plant Through Conceptual Change Approach

This study investigated the effectiveness of combining conceptual change text and discussion web strategies on students' understanding of photosynthesis and respiration in plants. Students' conceptual understanding of photosynthesis and respiration in plants was measured using the two-tier diagnostic test developed by Haslam and Treagust (1987, Journal of Biological Education 21: 203--211). The test was administered as pretest and posttest to a total of 233 eighth-grade students in six intact classes of the same school located in an urban area. The test of logical thinking was used to determine the reasoning ability of students. The experimental group was a class of 116 students received discussion web and conceptual change text instruction. A class of 117 students comprised the control group received a traditional instruction. After instruction, data were analyzed with two-way analysis of covariance (ANCOVA) using the Test of Logical Thinking and pretest scores as covariate. The conceptual change instruction, which explicitly dealt with students' misconceptions, produced significantly greater achievement in understanding of photosynthesis and respiration in plant concepts. Analysis also revealed a significant difference between performance of females and that of males in the favor of females, but the interaction of treatment with gender difference was not significant for learning the concepts.     

Perception,imagery, visualization and engineering graphics

We have conducted action research involving an instructional intervention over a 20-year period. This has demonstrated that spatial ability influences academic performance in engineering, and can be increased through instruction focused on using perception and mental imagery in three-dimensional representation. Prior to our intervention, the first-year engineering graphics course at our university had a failure rate of 36% for all engineering students and failure rates of 80% for African students studying at our university. Similar high failure rates were reported in engineering drawing and design courses at other Southern African universities, and similar association between low scores on tests of spatial ability and academic performance, suggesting that the problem was one encountered by many engineering students, not just by students at our university. Over the initial 2 years of the intervention, pass rates for the first-year engineering graphics course increased from 64 to 76%. With further changes in teaching, and the training of senior students as tutors to support the lecturing and practical activities provided in the course, the pass rates have risen to 88% annually, over a period in which the composition of the first-year student has become increasingly diverse, with greater numbers of students entering the university from disadvantaged educational backgrounds. The instructional model we have used is based on Piagetian principles, and confirms Piaget's theories with respect to the trainability of spatial ability in adulthood. Our findings suggest the importance of early identification of students with difficulty, as well as the potential value of an intervention aimed at training the processes involved in visualization through three-dimensional modelling and representation of objects. While spatial ability appears to be trainable through the methods we have developed, our research also indicates that level of spatial ability at time of intake to university is an important influence on academic performance, suggesting the value of instruction in visualization and three-dimensional representation at school level. Social factors are also important influences on academic performance, suggesting the value of tutorial-based interventions aimed at improving spatial ability in those university and technikon courses for which visualization and three-dimensional representation are a requirement.     

The Effect of Cooperative Learning Approach Based on Conceptual Change Condition on Students' Understanding of Chemical Equilibrium Concepts

The purpose of this study is to investigate the effects of the cooperative learning approach based on conceptual change conditions over traditional instruction on 10th grade students' conceptual understanding and achievement of computational problems related to chemical equilibrium concepts. The subjects of this study consisted of 87 tenth grade students from two intact classes of a Chemistry Course instructed by the same teacher. One of the classes was randomly assigned as the experimental group, which was instructed with cooperative learning approach based on conceptual change conditions and the other class was assigned as the control group, which was instructed with traditional instruction. Chemical Equilibrium Concept Test (CECT) was administered to the experimental and the control groups as pre- and post-tests to measure the students' conceptual understanding, and Chemical Equilibrium Achievement Test (CEAT) was administered to the experimental and the control groups as a post-test to measure the students' achievements related to computational problems. Science Process Skills Test was used at the beginning of the study to determine the students' science process skills. Multivariate Analysis of Covariate (MANCOVA) was used to analyze the data. The results showed that students in the experimental group had better conceptual understanding, and achievement of computational problems related to the chemical equilibrium concepts. Furthermore, students' science process skills were accounted for a significant portion of variations in conceptual understanding and achievements related to the computational problems.     

Improved application of the control-of-variables strategy as a collateral benefit of inquiry-based physics education in elementary school

In a quasi-experimental classroom study, we longitudinally investigated whether inquiry-based, content-focused physics instruction improves students’ ability to apply the control-of-variables strategy, a domain-general experimentation skill. Twelve third grade elementary school classes (Mdn_age = 9 years, N = 189) were randomly assigned to receive either four different physics curriculum units (intervention) or traditional instruction (control). Experiments were frequent elements in the physics units; however, there was no explicit instruction of the control-of-variables strategy or other experimentation skills. As intended, students in the intervention classes strongly increased their conceptual physics knowledge. More importantly, students in the intervention classes also showed stronger gains in their ability to apply the control-of-variables strategy correctly in novel situations compared to students in the control classes. Thus, a high dose of experimentation had the collateral benefit of improving the transfer of the control-of-variables strategy. The study complements lab-based studies with convergent findings obtained in real classrooms.     

Spatial visualization, visual imagery, and mathematical problem solving of students with varying abilities

The purpose of this study was to investigate students' use of visual imagery and its relationship to spatial visualization ability while solving mathematical word problems. Students with learning disabilities (LD), average achievers, and gifted students in sixth grade (N = 66) participated in this study. Students were assessed on measures of mathematical problem solving, visual imagery representation, and spatial visualization ability. The results indicated that gifted students performed better on both spatial visualization measures than students with LD and average-achieving students. Use of visual images was positively correlated with higher mathematical word-problem-solving performance. Furthermore, the use of schematic imagery was significantly and positively correlated with higher performance on each spatial visualization measure; conversely, it was negatively correlated with the use of pictorial images.     

High school students' understanding of projectile motion concepts

The aim of this study was to investigate the effectiveness of conceptual change-based instruction and traditionally designed physics instruction on students' understanding of projectile motion concepts. Misconceptions related to projectile motion concepts were determined by related literature on this subject. Accordingly, the Projectile Motion Concepts Test was developed. The data were obtained through 43 students in an experimental group taught with learning activities based on conceptual change instruction and 39 students in a control group who followed traditional classroom instruction. The results showed that conceptual change-based instruction caused significantly better acquisition of conceptual change of projectile motion concepts than the traditional instruction.     

Effect of explicit problem solving instruction on high school students' problem-solving performance and conceptual understanding of physics

In this study a two-sample, pre/posttest, quasi-experimental design was used to investigate the effect of explicit problem-solving instruction on high school students' conceptual understanding of physics. Eight physics classes, with a total of 145 students, were randomly assigned to either a treatment or comparison group. The four treatment classes were taught how to use an explicit problem-solving strategy, while the four comparison classes were taught how to use a textbook problem-solving strategy. Students' problem-solving performance and conceptual understanding were assessed both before and after instruction. The results indicated that the explicit strategy improved the quality and completeness of students' physics representations more than the textbook strategy, but there was no difference between the two strategies on match of equations with representations, organization, or mathematical execution. In terms of conceptual understanding, there was no overall difference between the two groups; however, there was a significant interaction between the sex of the students and group. The explicit strategy appeared to benefit female students, while the textbook strategy appeared to benefit male students. The implications of these results for physics instruction are discussed. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 551–570, 1997.     

The role of visualization in learning from computer‐based images

Among the sciences, the practice of geology is especially visual. To assess the role of spatial ability in learning geology, we designed an experiment using: (1) web‐based versions of spatial visualization tests, (2) a geospatial test, and (3) multimedia instructional modules built around QuickTime Virtual Reality movies. Students in control and experimental sections were administered measures of spatial orientation and visualization, as well as a content‐based geospatial examination. All subjects improved significantly in their scores on spatial visualization and the geospatial examination. There was no change in their scores on spatial orientation. A three‐way analysis of variance, with the geospatial examination as the dependent variable, revealed significant main effects favoring the experimental group and a significant interaction between treatment and gender. These results demonstrate that spatial ability can be improved through instruction, that learning of geological content will improve as a result, and that differences in performance between the genders can be eliminated.     

Visualizing time: how linguistic metaphors are incorporated into displaying instruments in the process of interpreting time-varying signals

Spatial visualization is a well-established topic of education research that has allowed improving science and engineering students’ skills on spatial relations. Connections have been established between visualization as a comprehension tool and instruction in several scientific fields. Learning about dynamic processes mainly relies upon static spatial representations or images. Visualization of time is inherently problematic because time can be conceptualized in terms of two opposite conceptual metaphors based on spatial relations as inferred from conventional linguistic patterns. The situation is particularly demanding when time-varying signals are recorded using displaying electronic instruments, and the image should be properly interpreted. This work deals with the interplay between linguistic metaphors, visual thinking and scientific instrument mediation in the process of interpreting time-varying signals displayed by electronic instruments. The analysis draws on a simplified version of a communication system as example of practical signal recording and image visualization in a physics and engineering laboratory experience. Instrumentation delivers meaningful signal representations because it is designed to incorporate a specific and culturally favored time view. It is suggested that difficulties in interpreting time-varying signals are linked with the existing dual perception of conflicting time metaphors. The activation of specific space–time conceptual mapping might allow for a proper signal interpretation. Instruments play then a central role as visualization mediators by yielding an image that matches specific perception abilities and practical purposes. Here I have identified two ways of understanding time as used in different trajectories through which students are located. Interestingly specific displaying instruments belonging to different cultural traditions incorporate contrasting time views. One of them sees time in terms of a dynamic metaphor consisting of a static observer looking at passing events. This is a general and widespread practice common in the contemporary mass culture, which lies behind the process of making sense to moving images usually visualized by means of movie shots. In contrast scientific culture favored another way of time conceptualization (static time metaphor) that historically fostered the construction of graphs and the incorporation of time-dependent functions, as represented on the Cartesian plane, into displaying instruments. Both types of cultures, scientific and mass, are considered highly technological in the sense that complex instruments, apparatus or machines participate in their visual practices.     

INVESTIGATING THE EFFECTIVENESS OF INQUIRY-BASED INSTRUCTION ON STUDENTS WITH DIFFERENT PRIOR KNOWLEDGE AND READING ABILITIES

This study examined the differential impacts of an inquiry-based instruction on conceptual changes across levels of prior knowledge and reading ability. The instrument emphasized four simultaneously important components: conceptual knowledge, reading ability, attitude toward science, and learning environment. Although the learning patterns and effect size analyses indicated that students from all subgroups demonstrated substantial gains on weather concepts, students from the low prior conceptual knowledge group demonstrated greater gains in conceptual knowledge than subgroups with more prior knowledge; and these gains remained stable 3 weeks after the instruction ceased. However, students from the low language proficiency group showed the least gains in conceptual knowledge. Students’ prior knowledge and reading ability were found to be positively and significantly associated to conceptual development. Recent perspectives on the role of language in science education and suggestions that support learning during instruction are briefly described.     

Comprehension of non-technical words in science: The case of students using a ‘foreign’ language as the medium of instruction

This paper reports on an investigation into Hong Kong students' comprehension of English non-technical words used in science. The investigation was conducted in a context in which English, a foreign language to students, is the medium of instruction, in that textbooks and examinations are all in English but the classroom language used is mainly Chinese, with frequent Chinese-English code-switching. A total of 4644 Secondary 4, 5 and 6 students participated in the study. Many students did not correctly comprehend a large proportion of the words, confused them with words that were graphologically or phonetically similar, and even took them for their antonyms. Such poor performance raises doubts as to whether the majority of Hong Kong students have attained a ‘threshold level’ of competence in English to benefit from learning science in English. Specializations: physics education, students' alternative conceptions in science, conceptual change, computer-assisted learning in physics.     

An Investigation of Effectiveness of Conceptual Change Text-oriented Instruction on Students' Understanding of Solution Concepts

This study investigated the effect of conceptual change text-oriented instruction over traditional instruction on students' understanding of solution concepts (e.g., dissolving, solubility, factors affecting solubility, concentrations of solutions, types of solutions, physical properties of solutions) and their attitudes towards chemistry. The sample of this study consisted of 87 undergraduate students from two classes enrolled in an introductory chemistry course. One of the classes was assigned randomly to the control group, and the other class were assigned randomly to the experimental group. During teaching the topic of solution concepts in the chemistry curriculum, a conceptual change text-oriented instruction was applied in the experimental group whereas traditional instruction was followed in the control group. The results showed that the students in the experimental group performed better with respect to solution concepts. In addition, it has been found that there was no significant difference between the attitudes of students in the experimental and control groups towards chemistry.     

物理图景素养的培养：模型、问题与对策

物理图景素养包括物理图景知识、方法、图景思维能力以及关于物理图景的情感态度价值观。物理图景素养同形象思维能力、创新思维能力和实践能力密切相关。通过调查问卷,笔者发现中学生的物理学习成绩与其物理图景素养水平之间呈现高度的正相关以及中学生的物理图景素养总体水平较低等问题。针对这些问题,提出注重观察与实验教学、注重培养学生运用物理图景解决问题的方式、习惯和能力、注重选用现代教育技术手段进行情景教学等建议。