• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.353-363
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• 2002

In this study, characteristics of the problem solving process of the balancing redox equations was ana-lyzed by mental capacity and problem solving methods, and the pertinent teaching and learning guidance for oxidation-reduction unit was suggested. Participants were 79 senior high school students and 57 science high school students. Tests were conducted to measure the mental capacity, the understanding of the oxidation-reduction concepts and the com-pletion of the balancing redox equations. The framework was made to find the patterns of failure and success. As the analysis of the influence on the performance of mental capacity,understanding of the oxidation-reduction concepts, and problem solving methods, students who had lower understanding of oxidation-reduction concepts selected the trial and error method, and their performance were influenced by mental capacity. The students that had higher understanding of the oxidation-reduction concepts had good performance by using oxidation number method regardless of their mental capacity. As the results of analysis for the patterns, the success patterns of solving the problems, those of mostly the sci-ence high school students, were the cases of using oxidation number method well and lessening problem solving steps. The patterns of failure in solving problems by using trial and error method showed that students had mistakes in cal-culating, errors in making unknown equations, no consideration for all variables, or stopped solving the complicated problems. The patterns of failure in solving problems by using oxidation number method showed that many students had wrong oxidation number or no consideration for mass and charge balance.

• Journal of The Korean Association For Science Education
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• v.29 no.2
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• pp.193-202
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• 2009

The purpose of this study was to investigate undergraduates' characteristics of problem-solving process through analysis of the response patterns on problem-solving laboratory. For this purpose, 18 freshmen taking a problem-solving-type general chemistry laboratory had been interviewed for the analysis of the characteristics of problem-solving process. According to the results, the students' responses have been classified into five types; trying to solve problems using new factors, trying to solve problems by finding missing factors in manual, recognizing problem-situations but just repeating the given process, not recognizing problem-situations but trying to solve doubts generated during execution, satisfying about results, and taking no further action. These results can be used as materials to suggest the role model of the students' laboratory execution and to look back on each students' execution.

• Journal of The Korean Association For Science Education
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• v.22 no.2
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• pp.252-260
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• 2002

The types and the characteristics of students' responses to anomalous data in studying 'boiling point' were investigated, and the degree of cognitive conflict and conceptual change were compared by students' cognitive variables. Tests regarding field dependence-independence and logical thinking ability, a preconception test, and a test of responses to anomalous data were administered to 137 sixth graders. Among them, 90 students whose preconceptions were consistent with the presented initial theory were selected. After learning the scientific concept, students' conceptual change was examined. Six types of responses identified were as follows: Rejection, reinterpretation, exclusion, uncertainty, belief decrease, and theory change. The main responses were rejection (33%) and theory change (39%). The results of Mann-Whitney U test indicated students who were field independent and had higher logical thinking abilities felt more cognitive conflict and exhibited more conceptual change.

• Journal of Educational Research in Mathematics
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• v.27 no.3
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• pp.511-536
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• 2017

The present study aims to investigate ways in which pre-service secondary mathematics teachers anticipate 1) students' responses to specific mathematical tasks which are chosen or devised by the participating pre-service teachers as requiring students' higher cognitive demand and, 2) their roles as math teachers to scaffold students' mathematical thinking. To achieve the goal, we had our pre-service teachers to engage in an adapted version of Spangler & Hallman-Thrasher(2014)'s Task Dialogue writing activity whose focus was to develop pre-service elementary teachers' ability to orchestrate mathematical discussion. 14 pre-service teachers who were junior at the time enrolled in the Mathematics Teaching Method Course were subjects of the current study. In-depth analysis of both Task Dialogues which pre-service secondary mathematics teachers wrote and audiotapes of the group discussions while they wrote the dialogues suggests the following results: First, the pre-service secondary teachers anticipated how students would approach a task based on their own teaching experiences. Second, they were challenged not only to anticipate more than one correct students' responses but to generate questions for the predicted correct-responses to bring forth students' divergent thinking. Finally, although they were aware that students' knowledge should be the crucial element guiding their decision-making process in teaching, they tended to lower the cognitive demands of tasks by providing students with too much guidance which brought forth the use of procedural knowledge. The study contributes to the field as it provides insights as to what to attend in designing teacher education course whose goal is to provide a foundation for developing pre-service teachers' ability to effectively orchestrate mathematical discussion.

• Journal of the Korean Chemical Society
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• v.64 no.5
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• pp.304-317
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• 2020

This study was conducted on four 11^th grade students at a high school in a small town to determine the effectiveness of responsive teaching. The three phases of the responsive teaching method proposed in the previous study were subdivided into six stages; Step 1 is elicitation of students' thoughts related to macroscopic world, Step 2 is drawing of students' early thoughts related to microscopic world, Step 3 is disciplinary connections with ideas of the particle, Step 4 is to clarify the learner's thoughts on the particle by the teacher's involvement, Step 5 is deepening students' thoughts, and Step 6 is expanding ideas. In Step 4, students came to the recognition that the cause of mass was atoms and that the cause of volume was molecules. In Step 5, students led to a shift in thinking that could ignore the volume of the molecules themselves through the properties of protons and neutrons that affect mass from a particle perspective. In the Step 6 of expanding ideas, students explained molecular motion by the concept of material point which ignores the volume of particles. This steps gave students perspectives on the relationship between the mass and volume of particles required by Avogadro's law. The students recognized that some systems could be studied only indirectly because they were too small, too large, too fast, or too slow to observe directly.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.212-224
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• 2007

Metabolism is one of the pivotal biology concepts, but many students have difficulty understanding it. The purposes of this study were (1) to explore 8th graders' conceptual change of an enzyme after classes of experimenting enzyme reaction and interpreting data using systematic analogies, (2) to discover the role of systematic analogies to enhance students' understanding, and (3) to explain students' difficulty understanding concepts as the ontological features. Systematic analogies were designed to encourage students to interpret their lab activities on enzyme reaction rates. Data were collected by using the pre-test and the post-test of open-ended form, students' worksheets, and interviews with students. After classes, the number of students to engender scientific conceptions about the function of enzyme, its structure, and its mechanism has increased. But more students failed to understand the reaction mechanisms having ontological features of equilibration processes than to understand the function of enzyme having ontological features of event-like processes. Even though the concepts of enzymes are hard to grasp owing to their ontological attributes of equilibration processes, a part of students' conceptions successfully progressed from the idea belonging to event-like processes to one belonging to equilibration processes. And systematic analogies were found to contribute in enhancing students' conceptual change of the enzyme reaction.

• Journal of The Korean Association For Science Education
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• v.25 no.2
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• pp.162-172
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• 2005

The purpose of this study was to examine the students' responses when students were confronted with anomalous situations in physics. 16 students were selected from one middle school in Busan by examining the pre-test results. To measure students' responses and cognitive conflict levels, written Cognitive Conflict Levels Test(CCLT) developed in a previous study was used together with interviews. Students' responses were tape-recorded. Two kinds of anomalous situations were presented. One was a quantitative demonstration with scale, the other was a qualitative demonstration without scale. In the quantitative group, all students observed anomalous situations correctly. However, in the qualitative group, many of their observations of anomalous situations were incorrect. The students who observed anomalous situations based on preconceptions tended not to abandon their preconceptions, and suggested confirmation experiments which were supposedly to support their preconceptions. The students who recognized results very differently from their preconceptions when confronted with anomalous situations abandoned their preconceptions and suggested alternative experiments. The students who changed their beliefs about preconceptions showed higher cognitive conflict levels than who didn't abandon their preconceptions.

• Communications of Mathematical Education
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• v.18 no.2 s.19
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• pp.239-250
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• 2004

수학적 힘의 함양과 문제해결력의 신장을 위한 수학교육에서 확률영역은 중요한 학습소재임에도 불구하고, 확률영역은 어려운 것으로 고착되었다. 이 연구에서는 학생들이 확률영역의 어떤 부분을 어려워하고 이해하기 힘들어하는지를 구체적 문항분석을 통하여 알아봄으로서 교수-학습의 기초자료를 제공하고자한다. 이를 위하여, 지난 10년간 출제되었던 대학수학능력시험의 확률영역 16문항을 고등학교 학생 220명에게 실시하고, 고전검사이론과 문항반응이론울 적용하여 그 결과를 분석하였다. 고전검사이론에서는 신뢰도와 변별도를 측정하였고, 문항반응이론에서는 Rasch 1-모수 문항반응모형에 근거한 BIGSTEP을 사용하여 내적타당도와 난이도를 측정하였다.

• Journal of Educational Research in Mathematics
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• v.19 no.2
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• pp.321-340
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• 2009

The purpose of this study was to analyze how lower graders in elementary school might respond to 4 different problem types in the context of measuring length: unit-length comparison, units and unit counting, unit-length expectation, and length comparison. A total of 375 students(185 second graders and 190 third graders) were surveyed and analyzed. The results showed that students were good at 'unit-length comparison' and 'units and unit counting', whereas they were not as to 'length comparison', This paper includes detailed analysis of students' responses as to both correct answer and incorrect one in conjunction with their typical answers and reasoning behind the answers. This paper suggests that teachers be sensitive to the certain level of reasoning tied to each type of problems and attend to students' difficulties in comparing length.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.465-475
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• 2015

The purpose of this study is to analyze the results of physics (optics) in nationwide standardized assessment and to investigate middle-school students' characteristics of achievement by using an option response rate distribution curve. For this purpose, we analyzed the 10 optics problems from the National Assessment of Educational Achievement (NAEA) items for middle school science subject conducted in 2010-2013. The results of this study are as follows; First, students showed a little higher achievement in optics than classical mechanics and electromagnetism. Second, students achieved significantly worse in 'formation of image' in 'light' part and 'variation of phase in propagation of wave' in 'wave' part. Third, students showed a context-dependent problem solving strategy and result. Additionally, we suggested some implications about the readjustment of some optics concepts level of national science curriculum, the need for teaching and learning strategies for basic level students, and the need for teaching and learning strategies focused on the realistic context.