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1.
This study involved the development and application of a two-tier diagnostic test measuring college biology students' understanding of diffusion and osmosis after a course of instruction. The development procedure had three general steps: defining the content boundaries of the test, collecting information on students' misconceptions, and instrument development. Misconception data were collected from interviews and multiple-choice questions with free response answers. The data were used to develop 12 two-tier multiple choice items in which the first tier examined content knowledge and the second examined understanding of that knowledge. The conceptual knowledge examined was the particulate and random nature of matter, concentration and tonicity, the influence of life forces on diffusion and osmosis, membranes, kinetic energy of matter, the process of diffusion, and the process of osmosis. The diagnostic instrument was administered to 240 students (123 non-biology majors and 117 biology majors) enrolled in a college freshman biology laboratory course. The students had completed a unit on diffusion and osmosis. The content taught was carefully defined by propositional knowledge statements, and was the same content that defined the content boundaries of the test. The split-half reliability was .74. Difficulty indices ranged from 0.23 to 0.95, and discrimination indices ranged from 0.21 to 0.65. Each item was analyzed to determine student understanding of, and identify misconceptions about, diffusion and osmosis.  相似文献   

2.
The purpose of this research was to investigate students' understanding of electrochemistry following a course of instruction. A list of conceptual and propositional knowledge statements was formulated to identify the knowledge base necessary for students to understand electric circuits and oxidation-reduction equations. The conceptual and propositional knowledge statements provided the framework for the development of a semistructured interview protocol which was administered to 32 students in their final year of high school chemistry. The interview questions about electric circuits revealed that several students in the sample were confused about the nature of electric current both in metallic conductors and in electrolytes. Students studying both physics and chemistry were more confused about current flow in metallic conductors than students who were only studying chemistry. In the section of the interview which focused on oxidation and reduction, many students experienced problems in identifying oxidation-reduction equations. Several misconceptions relating to the inappropriate use of definitions of oxidation and reduction were identified. The data illustrate how students attempted to make sense of the concepts of electrochemistry with the knowledge they had already developed or constructed. The implications of the research are that teachers, curriculum developers, and textbook writers, if they are to minimize potential misconceptions, need to be cognizant of the relationship between physics and chemistry teaching, of the need to test for erroneous preconceptions about current before teaching about electrochemical (galvanic) and electrolytic cells, and of the difficulties experienced by students when using more than one model to explain scientific phenomena.  相似文献   

3.
This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test procedure as described by Treagust constitutes the framework for this study. To differentiate a lack of knowledge from a misconception, a certainty response index is added as a third tier to each item. Based on propositional knowledge statements, related literature, and the identified misconceptions gathered initially from 157 pre-service teachers, the AREPDiT was constructed and administered to 256 pre-service teachers. The Cronbach alpha reliability coefficient of the pre-service teachers’ scores was estimated to be 0.74. Content and face validations were established by senior experts. A moderate positive correlation between the participants’ both-tiers scores and their certainty scores indicated evidence for construct validity. Therefore, the AREPDiT is a reliable and valid instrument not only to identify pre-service teachers’ misconceptions about GW, GE, OLD, and AR but also to differentiate these misconceptions from lack of knowledge. The results also reveal that a majority of the respondents demonstrated limited understandings about atmosphere-related environmental problems and held six common misconceptions. Future studies could test the AREPDiT as a tool for assessing the misconceptions held by pre-service teachers from different programs as well as in-service teachers and high school students.  相似文献   

4.
This research investigated students' understanding of electrochemistry following a 7–9-week course of instruction. A list of conceptual and propositional knowledge statements was formulated, and this provided the framework for semistructured interviews that were conducted with 32 students in their final year of high school chemistry, following instruction in electrochemistry. Three misconceptions identified in this study and five which have been reported earlier are incorporated into an alternative framework about electric current. The framework is grounded on the notion that a current always involves drifting electrons, even in solution. Another area where students' misconceptions were prevalent was in relation to the sign of the anode and cathode. Students who thought the anode was negatively charged believed cations would move toward it, and those who thought it was positively charged were unable to explain why electrons move away from it. Electrolytic cells also proved troublesome for students. Many students did not associate the positions of the anode and cathode with the polarity of the applied electromotive force (e.m.f.). Other students attempted to reverse features of electrochemical cells and apply the reversals to electrolytic cells. The implications of the research relate to students' interpretation of the language that is used to describe scientific phenomena and the tendency for students to overgeneralize, due to comments made by teachers or statements in textbooks.  相似文献   

5.
Chemical bonding is one of the key and basic concepts in chemistry. The learning of many of the concepts taught in chemistry, in both secondary schools as well as in the colleges, is dependent upon understanding fundamental ideas related to chemical bonding. Nevertheless, the concept is perceived by teachers, as well as by learners, as difficult, with teaching commonly leading to students developing misconceptions. Many of these misconceptions result from over‐simplified models used in text books, by the use of traditional pedagogy that presents a rather limited and sometimes incorrect picture of the issues related to chemical bonding and by assessments of students' achievement that influence the way the topic is taught. In addition, there are discrepancies between scientists regarding key definitions in the topic and the most appropriate models to teach it. In particular, teaching models that are intended to have transitional epistemological value in introducing abstract ideas are often instead understood by students as accounts of ontological reality. In this review paper we provide science educators, curricula developers and pre‐service and in‐service professional development providers an up‐to‐date picture regarding research and developments in teaching about chemical bonding. We review the external and internal variables that might lead to misconceptions and the problematic issue of using limited teaching/learning models. Finally, we review the approaches to teaching the concept that might overcome some of these misconceptions.  相似文献   

6.
Researchers have shown a growing interest in science teachers’ professional knowledge in recent decades. The article focuses on how chemistry teachers impart chemical bonding, one of the most important topics covered in upper secondary school chemistry courses. Chemical bonding is primarily taught using models, which are key for understanding science. However, many studies have determined that the use of models in science education can contribute to students’ difficulties understanding the topic, and that students generally find chemical bonding a challenging topic. The aim of this study is to investigate teachers’ knowledge of teaching chemical bonding. The study focuses on three essential components of pedagogical content knowledge (PCK): (1) the students’ understanding, (2) representations, and (3) instructional strategies. We analyzed lesson plans about chemical bonding generated by 10 chemistry teachers with whom we also conducted semi-structured interviews about their teaching. Our results revealed that the teachers were generally unaware of how the representations of models they used affected student comprehension. The teachers had trouble specifying students’ difficulties in understanding. Moreover, most of the instructional strategies described were generic and insufficient for promoting student understanding. Additionally, the teachers’ rationale for choosing a specific representation or activity was seldom directed at addressing students’ understanding. Our results indicate that both PCK components require improvement, and suggest that the two components should be connected. Implications for the professional development of pre-service and in-service teachers are discussed.  相似文献   

7.
Abstract

This study assessed 4th, 8th, and 11th grade students' understanding of natural and social science concepts related to pollution. A representative sample of public school students (n = 105) in 11 Maine schools was selected, and students were interviewed on four concept principles considered critical to a full understanding of the pollution problem. The concept of pollution included the much publicized issues of solid and toxic waste as well as air, soil, and water pollution. Research assertions were summarized in generalized correct concept statements indicating the extent of current student knowledge. Common misconceptions were also noted.

This study considered student understanding from a human ecological perspective, that is, as an integrated set or cluster of concepts related to pollution. This reflects a complex, integrated, and multidisciplinary conception of natural phenomena. Human constructivism, meaningful learning theory, and principles related to the relevance of student schema in the design of curriculum and instructional strategies guided this work.

The results of this study have implications for teaching about pollution and the design of science education curriculum materials based upon student knowledge. This information can guide teaching strategies concerning current environmental problems and thus help learners gain an appreciation for the complex and multi-disciplinary nature of science, technology, and society and how they affect the environment.  相似文献   

8.
Abstract

This study assessed the level of scientific and natural resource knowledge that fourth-, eighth-, and eleventh-grade students in Maine possess concerning acidic deposition. A representative sample of public school students (N = 175) was interviewed on twelve concept principles considered critical to a full understanding of the acidic deposition problem. These included geological, meteorological, ecological, political, and economic concepts. Student knowledge was rated for each concept principle on a scale of complete, high partial, low partial, or no understanding. Common misconceptions were also noted. Generalized correct concept statements of current student knowledge are reported, as well as generalized missing concepts. Our conclusions have implications for teaching about acidic deposition and the design of environmental education curriculum materials based upon student knowledge. This information can help teachers better instruct students about current environmental problems and thus help learners gain an appreciation for the complex and multidisciplinary nature of science and the environment.  相似文献   

9.
This paper presents findings from a case study into the development of student understanding of a complex and abstract scientific concept: chemical bonding. The case study reveals significant progression in student understanding, but also highlights issues of how such progression should be addressed. Particular emphasis is given to the factors that were associated with ‘blocks’ to appropriate concept development. The learner discussed had her own ‘alternative conceptions’ of ionic charge and electrostatic attraction that, lacking the appropriate background knowledge, she used in order to make sense of chemistry. These alternative ideas blocked the development of an electrostatic framework for bonding to replace the ‘full outer shell heuristic’ used at the General Certificate of Secondary Education (GCSE) level, and had repercussions for the understanding of a range of related concepts. The importance of diagnosing learners’ alternative ideas is thus demonstrated, and some of the problems of carrying out such diagnoses are considered.  相似文献   

10.
We have developed and validated a tool for assessing understanding of a selection of fundamental concepts and basic knowledge in undergraduate introductory molecular and cell biology, focusing on areas in which students often have misconceptions. This multiple-choice Introductory Molecular and Cell Biology Assessment (IMCA) instrument is designed for use as a pre- and posttest to measure student learning gains. To develop the assessment, we first worked with faculty to create a set of learning goals that targeted important concepts in the field and seemed likely to be emphasized by most instructors teaching these subjects. We interviewed students using open-ended questions to identify commonly held misconceptions, formulated multiple-choice questions that included these ideas as distracters, and reinterviewed students to establish validity of the instrument. The assessment was then evaluated by 25 biology experts and modified based on their suggestions. The complete revised assessment was administered to more than 1300 students at three institutions. Analysis of statistical parameters including item difficulty, item discrimination, and reliability provides evidence that the IMCA is a valid and reliable instrument with several potential uses in gauging student learning of key concepts in molecular and cell biology.  相似文献   

11.
This paper describes a case study focusing on the subject matter knowledge, pedagogical content knowledge, and beliefs about science teaching of student teachers in Turkey at the start of their university education. The topic of interest was that of teaching chemical reactions in secondary chemistry education. A written test was developed which used the research literature on potential student misconceptions with regard to different aspects of chemical reactions. Thirty beginning science student teachers were tested, with an additional eight interviews from the student teachers in the same sample. The interviews focused on student teachers’ views about how to best teach chemical reactions in lower secondary chemistry classes. The results revealed deficits in the subject matter knowledge of the student teachers. It also became obvious that the teachers in this sample held very traditional and teacher-centred beliefs when it came to chemistry teaching at the secondary level. Their teaching attitudes were geared mainly towards the acquisition of facts by pupils, and often ignored the development of process-oriented skills. Implications for science teacher education are discussed.  相似文献   

12.
This study involved the development and application of a two-tier diagnostic test measuring students understanding of flowering plant growth and development. The instrument development procedure had three general steps: defining the content boundaries of the test, collecting information on students misconceptions, and instrument development. Misconception data were collected from interviews and multiple-choice questions with open response answers. The data were used to develop 13 two-tier multiple-choice items. The conceptual knowledge examined was flowering plant life cycles, reproduction, precondition of germination, plant nutrition, and mechanism for growth and development. The diagnostic instrument was administered to 477 high school students. The correlation coefficient of test-retest was 0.75. Difficulty indices ranged from 0.24 to 0.82, and discrimination indices ranged from 0.32 to 0.65. Results of the Flowering Plant Growth and Development Diagnostic Test suggested that students did not acquire a satisfactory understanding of plant growth and development concepts. Nineteen misconceptions were identified through analysis of the items that could inform biology instruction and resource.  相似文献   

13.
Correlation is an essential concept in statistics; however, students may hold misconceptions about correlation, even after receiving instruction. This study aimed to elucidate (1) the misconceptions held by senior high school students about correlation, using the tool of concept mapping along with interviewing, (2) the possible causes of these misconceptions, and (3) the effectiveness, advantages, and limitations of the adopted concept mapping using an interviewing technique for identifying student misconceptions. Twenty-five grade-12 students who had received tuition on correlation were the subjects of this study. Concept mapping through interviewing was used to collect and analyze data in order to identify the subjects’ misconceptions, and their possible causes. The major study results are as follows. (1) Seven misconceptions about correlation were detected. Of these seven misconceptions, five were newly discovered by this study, while the other two are similar to those found by previous studies. Each of the seven misconceptions was held by 20–68% of the subjects, showing their prevalence and significance. (2) Four major factors related to the development of misconceptions about correlation were identified: learning materials, language, daily-life experiences, and existing mathematical concepts. (3) The concept mapping through the interviewing technique adopted in this study was effective in detecting misconceptions about statistics, especially in revealing new misconceptions, and it was also helpful in exploring their possible causes. However, tremendous effort and the time consumed are the major limitations of this technique. (4) The paper concluded by providing some recommendations for researchers and educators.  相似文献   

14.
In this study, concept map activities were used to trigger group discussions about inclusive education, with a focus on learners with disabilities. The participants were 226 Tanzanian student teachers. This article reports and discusses how the maps were analysed and what they indicate about the students’ thinking about certain aspects of inclusive education. The results also indicate that concept mapping as an activity in teacher education may be useful and engaging for students. It may help them to organise knowledge and make them aware of their own and others’ understanding of inclusive education practices. An analysis of concept maps constructed by student teachers may also help lecturers to identify views, misconceptions, knowledge gaps and insights about inclusion in education settings.  相似文献   

15.
This study investigated the quality and extent of understanding of certain well-known theoretical concepts which prospective teachers of chemistry in Yemen possess. In addition to the concepts of the conservation of atoms and mass, and the mole, the concepts of atomic mass and balancing chemical equations were chosen for this study. An instrument was built first, then administered to 173 junior and senior prospective chemistry teachers. The results showed that the prospective teachers' understandings of most of the concepts ranged from a partial understanding with specific misconception to no understanding. Only on balancing chemical equations did the prospective teachers show good understanding. The results showed that most prospective teachers depended on mere memorization of the concepts without meaningful understanding. It also found that the prospective teachers' knowledge about the concepts was fragmented and not correlated. The study attributed the prospective teachers' misconceptions to defective instruction. Finally, the study concluded that more effective teaching methods are needed to ensure a sound understanding of these concepts. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 181–197, 1997.  相似文献   

16.
We describe the development and validation of a three-tiered diagnostic test of the water cycle (DTWC) and use it to evaluate the impact of prior learning experiences on undergraduates’ misconceptions. While most approaches to instrument validation take a positivist perspective using singular criteria such as reliability and fit with a measurement model, we extend this to a multi-tiered approach which supports multiple interpretations. Using a sample of 130 undergraduate students from two colleges, we utilize the Rasch model to place students and items along traditional one-, two-, and three-tiered scales as well as a misconceptions scale. In the three-tiered and misconceptions scales, high confidence was indicative of mastery. In the latter scale, a ‘misconception’ was defined as mastery of an incorrect concept. We found that integrating confidence into mastery did little to change item functioning; however, three-tiered usage resulted in higher reliability and lower student ability estimates than two-tiered usage. The misconceptions scale showed high efficacy in predicting items on which particular students were likely to express misconceptions, and revealed several tenacious misconceptions that all students were likely to express regardless of ability. Previous coursework on the water cycle did little to change the prevalence of undergraduates’ misconceptions.  相似文献   

17.
Recursion is both an important and a difficult topic for introductory Computer Science students. Students often develop misconceptions about the topic that need to be diagnosed and corrected. In this paper, we report on our initial attempts to develop a concept inventory that measures student misconceptions on basic recursion topics. We present a collection of misconceptions and difficulties encountered by students when learning introductory recursion as presented in a typical CS2 course. Based on this collection, a draft concept inventory in the form of a series of questions was developed and evaluated, with the question rubric tagged to the list of misconceptions and difficulties.  相似文献   

18.
Educational researchers and teachers are well aware that misconceptions—erroneous ideas that differ from the scientifically accepted ones—are very common amongst students. Daily experiences, creative and perceptive thinking and science textbooks give rise to students' misconceptions which lead them to draw erroneous conclusions that become strongly attached to their views and somehow affect subsequent learning. The main scope of this study was to understand what students consider a mineral to be and why. Therefore, the goals were (1) to identify eleventh-grade students' misconceptions about the mineral concept; (2) to understand which variables (gender, parents' education level and attitude towards science) influenced students' conceptions; and (3) to create teaching tools for the prevention of misconceptions. In order to achieve these goals, a diagnostic instrument (DI), constituted of a two-tier diagnostic test and a Science Attitude Questionnaire, was developed to be used with a sample of 89 twelfth-grade students from five schools located in central Portugal. As far as we know, this is the first DI developed for the analysis of misconceptions about the mineral concept. Data analysis allows us to conclude that students had serious difficulties in understanding the mineral concept, having easily formed misconceptions. The variables gender and parents' education level influence certain students' conceptions. This study provides a valuable basis for reflection on teaching and learning strategies, especially on this particular theme.  相似文献   

19.
This study examines differences in conceptual knowledge representations among three groups of students with different levels of study of chemistry. Variation in the structural characteristics of participants’ concept maps on the topic of acid-base equilibrium were sought by indirect means. Year 12 secondary chemistry students, undergraduate chemistry majors and honours, masters and doctoral candidates participated in the study. Paired propositional links in the concept maps for the three groups were analysed by the scaling algorithms “Pathfinder” and multidimensional scaling. Results show differences among groups in the structural significance in the networks of abstract process-related nodes and matter-related nodes. Implications for theories of conceptual change are discussed.  相似文献   

20.
The central goal of this study was to create a new diagnostic tool to identify organic chemistry students’ alternative conceptions related to acid strength. Twenty years of research on secondary and college students’ conceptions about acids and bases has shown that these important concepts are difficult for students to apply to qualitative problem solving. Yet, few published studies document how students’ prior knowledge of acids influences their understanding of acid strength in organic chemistry contexts. We developed a nine-item multiple-tier, multiple-choice concept inventory to identify alternative conceptions that organic chemistry students hold about acid strength, to determine the prevalence of these conceptions, and to determine how strongly these conceptions bias student reasoning. We identified two significant alternative conceptions that organic chemistry students hold about acid strength. Students who answered items incorrectly were more confident about their answers than peers who answered items correctly, suggesting that after one semester of organic chemistry, students do not know what they do not know. Implications for the teaching of acid strength are discussed.  相似文献   

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