IMPACT OF A REPRESENTATIONAL APPROACH ON STUDENTS’ REASONING AND CONCEPTUAL UNDERSTANDING IN LEARNING MECHANICS

The aim of this study was to explore whether a representational approach could impact on the scores that measure students’ understanding of mechanics and their ability to reason. The sample consisted of 24 students who were undergraduate, preservice physics teachers in the State University of Malang, Indonesia. The students were asked to represent a claim, provide evidence for it, and then, after further representational manipulations, refinement, discussion, and critical thought, to reflect on and confirm or modify their original case. Data analysis was based on the pretest–posttest scores and students’ responses to relevant phenomena during the course. The results showed that students’ reasoning ability significantly improved with a d-effect size of 2.58 for the technical aspects and 2.51 for the conceptual validity aspects, with the average normalized gain being 0.62 (upper–medium) for the two aspects. Students’ conceptual understanding of mechanics significantly improved with a d-effect size of about 2.50 and an average normalized gain of 0.63. Students’ competence in mechanics shifted significantly from an under competent level to mastery level. This paper addresses statistically previously untested issues in learning mechanics through a representational approach and does this in a culture that is quite different from what has been researched so far using student-generated representational learning as a reasoning tool for understanding and reasoning.     

THE IMPACT OF PEER INSTRUCTION ON COLLEGE STUDENTS’ BELIEFS ABOUT PHYSICS AND CONCEPTUAL UNDERSTANDING OF ELECTRICITY AND MAGNETISM

The purpose of this study is to assess students’ conceptual learning of electricity and magnetism and examine how these conceptions, beliefs about physics, and quantitative problem-solving skills would change after peer instruction (PI). The Conceptual Survey of Electricity and Magnetism (CSEM), Colorado Learning Attitudes about Science Survey (CLASS), multiple-choice test was administered as a pre- and posttest with Solomon 4 group design to students (N  =  138) enrolled on freshman level physics course. The number of chapter taught to the students was 14. Problem-solving strategy steps were asked to students in the exam. The analyses of CSEM showed that the treatment group (g  =  0.62) obtained significantly higher conceptual learning gain than the control group (g  =  0.36). The conceptual understanding and problem-solving skills of the students on magnetism considerably enhanced when PI was conducted (37% and 20%, respectively). CLASS results for 5 subscales (conceptual understanding, applied conceptual understanding, problem solving general, problem solving confidence, and problem solving sophistication) supported the findings of CSEM.     

THAI GRADE 10 AND 11 STUDENTS’ UNDERSTANDING OF STOICHIOMETRY AND RELATED CONCEPTS

The research reported in this case study explores the understanding of stoichiometry and related concepts of Thai science students in grades 10 and 11 after major national curriculum reforms. Students’ conceptions and alternative conceptions were investigated using a questionnaire - the Stoichiometry Concept Questionnaire (SCQ) (N = 97), which consists of 16 multiple-choice items, the choices for which respondents are required to provide reasons. The findings suggest that less than half of the students surveyed hold what is considered by a panel of experts to be a scientifically acceptable understanding for the conceptions investigated. The main student alternative conceptions are that one mole of all substances has a volume of 22.4 L at STP, that a solution that contains a greater mass of solute has the higher molar concentration, and that the limiting reagent is the reagent for which the lowest mass of reactant is present. Examination of students’ reasons suggests that they resort to the use of algorithms with little understanding of the underlying concepts. It thus seems the national educational reforms have not resulted in a sound understanding of some science concepts. It is recommended that curriculum developers should specify a need for conceptual understanding along with capability in numerical problem-solving in their learning objectives, and link this to assessment regimes that reward conceptual understanding. A need for on-going professional development seems essential if the intentions of the Thai curriculum reforms are to be realized.     

STUDENTS’ UNDERSTANDING OF EQUILIBRIUM AND STABILITY: THE CASE OF DYNAMIC SYSTEMS

Engineering students in control courses have been observed to lack an understanding of equilibrium and stability, both of which are crucial concepts in this discipline. The introduction of these concepts is generally based on the study of classical examples from Newtonian mechanics supplemented with a control system. Equilibrium and stability are approached in different ways at the various stages of a typical engineering syllabus: at the beginning, they are mostly dealt with a static point of view, for example in mechanics, and are subsequently handled through dynamic analysis in control courses. In general, there is a little clarification of the differences between these concepts or the ways in which they are linked. We believe that this leads to much confusion and incomprehension among engineering students. Several studies have shown that students encounter difficulties when presented with simple familiar or academic static equilibrium cases in mechanics. Our study investigates students’ conceptions and misconceptions about equilibrium and stability through a series of questions about several innovative non-static situations. It reveals that the understanding of these notions is shaken when the systems being studied are placed in inertial or non-inertial moving reference frames. The students in our study were particularly uncertain about the existence of unstable equilibrium positions and had difficulty in differentiating between the two concepts. The results suggest that students use a velocity-based approach to explain such situations. A poor grasp of the above fundamental concepts may result from previous learning experiences. More specifically, certain difficulties seem to be directly linked to a lack of understanding of these concepts, while others are related to misconceptions arising from everyday experiences and the inappropriate use of physical examples in primary school.     

DIAGNOSING STUDENTS’ UNDERSTANDING OF ENERGY AND ITS RELATED CONCEPTS IN BIOLOGICAL CONTEXT

This study diagnosed the understanding about energy and biological-context energy concepts held by 90 first-year South African university biology students. In particular, students’ explanations of energy in a biological context, how energy is involved in different biological situations and whether energy is present and what types of energy are involved in diagrams depicting biological phenomena were investigated. The pencil-and-paper diagnostic test, specifically designed for this study, was used to elicit students’ understanding using test items involving biological phenomena. The results showed that many students had problems in understanding energy and energy-related concepts in the following areas: First, the majority of the students provided definitions of energy rather than the explanations they were asked to provide, and the definition could have been rote-learned. Second, although nearly all students knew the energy conservation principle (energy cannot be created or destroyed), many of them were unable to apply this concept to biological contexts. Third, many students erroneously claimed that the energy for metabolism and life processes is made available during photosynthesis in plants, during digestion in animals or that this energy comes directly from the sun. Fourth, about two thirds of the students erroneously indicated that there is no energy involved/present in inanimate objects such as a statue. The implications for the teaching and learning of energy and its related concepts and recommendations for further research are discussed.     

PROMOTING STUDENTS’ CONCEPTUAL UNDERSTANDING OF PLANT DEFENSE RESPONSES USING THE FIGHTING PLANT LEARNING UNIT (FPLU)

Most students think animals are more interesting than plants as a study topic believing that plants are inferior to animals because they are passive and unable to respond to external challenges, particularly biological invaders such as microorganisms and insect herbivores. The purpose of this study was to develop an inquiry-based learning unit, the Fighting Plant Learning Unit (FPLU), which focuses on plant defense responses to biological stimuli. The study also investigated students’ perceptions of the FPLU implemented in a constructivist classroom. A total of 31 Thai science majors from grade 12 participated in this study. Multiple data-gathering techniques (quantitative and qualitative) were employed: conceptual testing, concept mapping, the Constructivist Learning Environment Survey questionnaire and semi-structured interviews. It was found that from their active participation, the students developed a better conceptual understanding of plant defense mechanisms. In addition, they appeared to have positive attitudes toward the FPLU as evidenced by their preference for inquiry-based teaching in a constructivist learning environment. Finally, their perspectives on and appreciation of plants as active organisms had been favorably changed by the experience.     

SECONDARY SCHOOL STUDENTS’ UNDERSTANDING OF MATHEMATICAL INDUCTION: STRUCTURAL CHARACTERISTICS AND THE PROCESS OF PROOF CONSTRUCTION

In this study, we investigate the meaning students attribute to the structure of mathematical induction (MI) and the process of proof construction using mathematical induction in the context of a geometric recursion problem. Two hundred and thirteen 17-year-old students of an upper secondary school in Greece participated in the study. Students’ responses in 3 written tasks and the interviews with 18 of them are analyzed. Though MI is treated operationally in school, the students, when challenged, started to recognize the structural characteristics of MI. In the case of proof construction, we identified 2 types of transition from argumentation to proof, interwoven in the structure of the geometrical pattern. In the first type, MI was applied to the algebraic statement that derived from the direct translation of the geometrical situation. In the second type, MI was embedded functionally in the geometrical structure of the pattern.     

STUDENTS’ UNDERSTANDING OF LARGE NUMBERS AS A KEY FACTOR IN THEIR UNDERSTANDING OF GEOLOGIC TIME

An understanding of geologic time is comprised of 2 facets. Events in Earth’s history can be placed in relative and absolute temporal succession on a vast timescale. Rates of geologic processes vary widely, and some occur over time periods well outside human experience. Several factors likely contribute to an understanding of geologic time, one of which is an individual’s ability to perceive the relative size of large time periods and to move multiplicatively through quantities that differ by many orders of magnitude. Thirty-five US students aged 13–24?years participated in task-based interviews to assess their understanding of large temporal periods. Fewer than half of the students performed well enough to indicate that their knowledge of large numbers was robust enough to enable them to understand processes in geologic time. Some students were confused about relationships between quantities in the thousands and millions, while others had difficulty showing proportional relationships among relatively small temporal units (up to 100?years). Students differed in their ability to perceive the entire scale upon which numbers were to be placed as well as broader problem-solving strategies. Spatial mapping of numbers was evident. Implications for future research are discussed.     

UNIVERSITY STUDENTS’ UNDERSTANDING OF THERMAL PHYSICS IN EVERYDAY CONTEXTS

Thermal physics is in the realm of everyday experience, underlies current environmental concerns, and underpins studies in sciences, health and engineering. In the state of NSW in Australia, the coverage of thermal topics in high school is minimal, and, hence, so is the conceptual understanding of students. This study takes a new approach at exploring conceptions of students with a qualitative analysis facilitated by NVivo complemented with reference to sociocultural ideas of learning. A 2-part pen and paper question was given to 598 first year university students of different educational backgrounds (and therefore physics expertise). ‘The Question’ was based on 2 familiar scenarios and required the selection of a concept first, followed by an explanation. The results showed that concepts were favoured based on a student’s everyday experience and their curriculum through high school, and some were more effective than others in making scientifically congruent responses. The reported thermal physics alternative conceptions were also examined in our sample, and students’ reasoning behind such conceptions indicate that some conceptions do not inhibit scientifically congruent responses whilst others do. The results implicate language and the everyday experiences of the student in the teaching and learning of thermal physics.     

HIGH SCHOOL STUDENTS’ PROFICIENCY AND CONFIDENCE LEVELS IN DISPLAYING THEIR UNDERSTANDING OF BASIC ELECTROLYSIS CONCEPTS

This study was conducted with 330 Form 4 (grade 10) students (aged 15??C?16?years) who were involved in a course of instruction on electrolysis concepts. The main purposes of this study were (1) to assess high school chemistry students?? understanding of 19 major principles of electrolysis using a recently developed 2-tier multiple-choice diagnostic instrument, the Electrolysis Diagnostic Instrument (EDI), and (2) to assess students?? confidence levels in displaying their knowledge and understanding of these electrolysis concepts. Analysis of students?? responses to the EDI showed that they displayed very limited understanding of the electrolytic processes involving molten compounds and aqueous solutions of compounds, with a mean score of 6.82 (out of a possible maximum of 17). Students were found to possess content knowledge about several electrolysis processes but did not provide suitable explanations for the changes that had occurred, with less than 45?% of students displaying scientifically acceptable understandings about electrolysis. In addition, students displayed limited confidence about making the correct selections for the items; yet, in 16 of the 17 items, the percentage of students who were confident that they had selected the correct answer to an item was higher than the actual percentage of students who correctly answered the corresponding item. The findings suggest several implications for classroom instruction on the electrolysis topic that need to be addressed in order to facilitate better understanding by students of electrolysis concepts.     

UNDERSTANDING STUDENTS�� OUT-OF-SCHOOL MATHEMATICS AND SCIENCE PRACTICE

This study examined standard 6 and 8 (Standards 6 and 8 are the sixth and eighth years, respectively, of primary level schooling in Kenya.) students’ perceptions of how they use mathematics and science outside the classroom in an attempt to learn more about students’ everyday mathematics and science practice. The knowledge of students’ everyday mathematics and science practice may assist teachers in helping students be more powerful mathematically and scientifically both in doing mathematics and science in school and out of school. Thirty-six students at an urban school and a rural school in Kenya were interviewed before and after keeping a log for a week where they recorded their everyday mathematics and science usage. Through the interviews and log sheets, we found that the mathematics that these students perceived they used outside the classroom could be classified as 1 of the 6 activities that Bishop (Educ Stud Math 19:179–191, 1988) has called the 6 fundamental mathematical activities and was also connected to their perception of whether they learned mathematics outside school. Five categories of students’ perceptions of their out-of-school science usage emerged from the data, and we found that 4 of our codes coincided with 2 activities identified by Lederman & Lederman (Sci Child 43(2):53, 2005) as part of the nature of science and 2 of Bishop’s categories. We found that the science these students perceived that they used was connected to their views of what science is.     

IMPACT OF INTERACTIVE MULTIMEDIA MODULE WITH PEDAGOGICAL AGENTS ON STUDENTS’ UNDERSTANDING AND MOTIVATION IN THE LEARNING OF ELECTROCHEMISTRY

The Electrochemistry topic is found to be difficult to learn due to its abstract concepts involving macroscopic, microscopic, and symbolic representation levels. Studies have shown that animation and simulation using information and communication technology (ICT) can help students to visualize and hence enhance their understanding in learning abstract chemistry topics. As a result, an interactive multimedia module with the pedagogical agent (IMMPA) named the EC Lab (Electrochemistry Lab) was developed in order to assist students in the learning of Electrochemistry topics. A non-equivalent pretest–posttest control group design investigation was carried out in order to gauge the effect of the IMMPA EC Lab on students’ understanding and motivation in the learning of Electrochemistry. Some 127 Form Four students from two secondary schools in one of the districts in Malaysia were involved in the study. Each school had one treatment group and one control group taught by the same Chemistry teacher. Instruments involved were a pre- and posttest, a pre- and post-motivation questionnaire, and the IMMPA EC Lab. Results showed a significant difference between the control groups and treatment groups in the understanding of concepts in the learning of Electrochemistry.     

SCIENCE AND NON-SCIENCE UNDERGRADUATE STUDENTS’ CRITICAL THINKING AND ARGUMENTATION PERFORMANCE IN READING A SCIENCE NEWS REPORT

A scientifically literate person should be able to engage and critique science news reports about socioscientific issues from a variety of information sources. Such engagement involves critical thinking and argumentation skills to determine if claims made are justified by evidence and explained by reasonable explanations. This study explored university students’ critical thinking performance when they read science news reports. Undergraduate science/applied science (n??=??52) and non-science (n??=??52) majors were asked to select a science news report from Internet sources and then to read, critique, and make comments about its contents. The science and non-science majors’ comments and their quality were identified and assessed in terms of analyzing the argument elements—claims and warrants, counterclaims and warrants, rebuttals, qualifiers, and evidence. The results indicated there is significant difference in identifying and formulating evidence favoring science/applied science over non-science majors (p??p??相似文献   

ELEMENTARY SCHOOL TEACHERS’ UNDERSTANDING OF THE MEAN AND MEDIAN

This study provides a snapshot of elementary school teachers’ understanding of the mean and median. The research is presented in light of recent work regarding preservice teachers’ understanding of the mean. Common misconceptions are identified which lead to potential implications for teacher preparation programs. One of the primary concerns regarding increasing the standards expected of students to learn statistics is teachers’ preparation to address those standards. Exploring issues with teachers’ understanding of two of the most prominent concepts in the enacted curriculum provides a glimpse into the need to adequately prepare teachers to teach statistics.     

LEARNERS’ AND TEACHERS’ CONCEPTUAL KNOWLEDGE OF SCIENCE PROCESSES: THE CASE OF BOTSWANA

The conceptual knowledge of science processes possessed by University of Botswana science students and senior secondary school science teachers was sought through a three-part questionnaire. One part requested demographic data of subjects, the second part asked them to select their level of familiarity with the processes, and the third part probed their conceptual definitions of the science processes. The definitions were scored as incorrect, partially correct and correct on an ordinal scale. Statistical analysis was done using Spearman rho correlation and one sample t test. The findings revealed that the science teachers did not have sufficient conceptual knowledge of science processes to help their students to understand in a meaningful way; both students’ and teachers’ views of their familiarity of science processes did not corroborate their demonstrated ability to provide acceptable conceptual definitions of the processes; there was no association between students’ and teachers’ conceptions of the science processes; and if conceptual knowledge of science processes was demanded, the entering students, who were the immediate graduates of the senior secondary schools, might not have enough to pursue tertiary level science courses. It is suggested that both conceptual and operational knowledge of science processes be required at secondary and tertiary levels of science education.     

IMPACT OF EXPLICIT PRESENTATION OF SLOPES IN THREE DIMENSIONS ON STUDENTS’ UNDERSTANDING OF DERIVATIVES IN MULTIVARIABLE CALCULUS

In two dimensions (2D), representations associated with slopes are seen in numerous forms before representations associated with derivatives are presented. These include the slope between two points and the constant slope of a linear function of a single variable. In almost all multivariable calculus textbooks, however, the first discussion of slopes in three dimensions (3D) is seen with the introduction of partial derivatives. The nature of the discussions indicates that authors seem to assume that students are able to naturally extend the concept of a 2D slope to 3D and correspondingly it is not necessary to explicitly present slopes in 3D. This article presents results comparing students that do not explicitly discuss slopes in 3D with students that explicitly discuss slopes in 3D as a precursor to discussing derivatives in 3D. The results indicate that students may, in fact, have significant difficulty extending the concept of a 2D slope to a 3D slope. And that the explicit presentation of slopes in 3D as a precursor to the presentation of derivatives in 3D may significantly improve student comprehension of topics of differentiation in multivariable calculus.

     

EVALUATING STUDENTS’ UNDERSTANDING OF KINETIC PARTICLE THEORY CONCEPTS RELATING TO THE STATES OF MATTER, CHANGES OF STATE AND DIFFUSION: A CROSS-NATIONAL STUDY

This paper reports on the understanding of three key conceptual categories relating to the kinetic particle theory: (1) intermolecular spacing in solids, liquids and gases, (2) changes of state and intermolecular forces and (3) diffusion in liquids and gases, amongst 148 high school students from Brunei, Australia, Hong Kong and Singapore using 11 multiple-choice items that required students to provide explanations for their selection of particular responses to the items. Students’ responses to the items revealed limited understanding of the particle theory concepts, with nine alternative conceptions held by more than 10% of various samples of students. Also, 40.5–78.4% of all students indicated consistent understanding relating to the three conceptual categories based on their responses to the 11 items. However, when their explanations were taken into account, very few students displayed consistent understanding of the related concepts.