• Journal of the Korean Chemical Society
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• v.58 no.6
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• pp.580-589
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• 2014

The concepts used to explain specific phenomenon can be influenced by context or coherent regardless of context. The purpose of this study is to understand middle school students' concept of particles in particular context and to investigate the effects of context on concept of particles. A conceptual questionnaire was developed to find out how students represented particles in two contexts: solid and solution states of electrolytes, and ion precipitation reaction. The questionnaire was administered to $9^{th}$ grade students after classes of 'electrolyte and ions' unit. The responses of students were analyzed using framework developed for categorization of students' concepts. The results are as follows: First, it was found that students used various concepts on particles when they explained solid and solution state of electrolytes, respectively. Second, we identified students' concepts of particles used to explain ion precipitation reaction. In addition, we recognized that majority of students failed to write correct chemical symbols. Third, approximately 79% of students showed coherent responses for explanation of particles in solution state of both electrolytes and ion precipitation reaction. About 57% of students had scientific concepts. Some suggestions were made based on results for acquisition of scientific concepts on particles in different contexts.

• Journal of The Korean Association For Science Education
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• v.32 no.10
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• pp.1524-1536
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• 2012

Science attitudes affect the quality of learning, and they are considered as one of the major concerns in science education. It is necessary to analyze the proximity between concepts with science attitudes. Accordingly, this study was designed to analyze the proximity of the concept related to photosynthesis as it changed after class according to the levels of science attitudes. A survey on the concept of photosynthesis and science attitudes before and after class was conducted on 270 7th-grade students. The concept of photosynthesis was composed of 'the place of photosynthesis,' 'products of photosynthesis,' 'reactants of photosynthesis,' and 'environmental factors.' The proximity of the concept of photosynthesis was analyzed through the utilization of multidimensional scaling (MDS). The research results were as follows: (1) Students changed the proximity between concepts by acquiring concrete concepts through class. (2) The upper group in science attitudes tends to be closer to the proximity between scientific concepts through class, compared to the intermediate and lower groups. (3) In all students with entire levels of science attitudes, non-scientific concepts continued to exist even after class, and the non-scientific concepts were deemed to interfere with the proximity between scientific concepts related to photosynthesis. (4) Students turned out to be aware of the concepts related to each other in four areas associated with photosynthesis. That is, it can be said that students are closely aware of the place where photosynthesis can occur and the materials needed as well as materials generated as a result of photosynthesis and the materials needed in terms of concepts related to photosynthesis.

• Journal of The Korean Association For Science Education
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• v.12 no.3
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• pp.77-89
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• 1992

According to many previous researches on the students' physics conceptions, in spite of school science learning the students' preconceptions were either not changed or reinforced. Although many researchers argued that the presentation of conflict situations which can not be explained by the students' preconceptions is prerequisite to their conceptual changes, some other researchers argued that such a presentation could be useless. In this study, a model of students' conceptual change in physics, which encourages students to recognize actively the conflicting situations and to control the process of their conceptual changes, was developed. In this model, the critical discussion on rival concepts and the reflective thinking were regarded as two important factors for students' conceptual changes.

• The Mathematical Education
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• v.41 no.3
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• pp.341-360
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• 2002

The purpose of the study was to investigate the effectiveness of dynamic software in solving high school analytic geometry problems compared with traditional algebraic approach. Three high school students who have revealed high performance in mathematics were involved in this study. It was considered that they mastered the basic concepts of equations of plane figure and curves of secondary degree. The research questions for the study were the followings: 1) In what degree students understand relationship between geometric approach and algebraic approach in solving geometry problems? 2) What are the difficulties students encounter in the process of using the dynamic software? 3) In what degree the constructions of geometric figures help students to understand the mathematical concepts? 4) What are the effects of dynamic software in constructing analytic geometry concepts? 5) In what degree students have developed the images of algebraic concepts? According to the results of the study, it was revealed that mathematical connections between geometric approach and algebraic approach was complementary. And the students revealed more rely on the algebraic expression over geometric figures in the process of solving geometry problems. The conceptual images of algebraic expression were not developed fully, and they blamed it upon the current college entrance examination system.

• Journal of Korean Elementary Science Education
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• v.32 no.4
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• pp.593-606
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• 2013

The purpose of this study was to examine the effect of science-based STEAM program using a portfolio on elementary students' formation of science concepts and investigate students' opinion about the program. The developed program was applied to 1 experimental class(10 boys and 12 girls) and general science lessons, using a science textbook, was applied to 1 controlled class(11 boys and 13 girls) of $5^{th}$ grade students at S elementary school in Seoul through a total 6 sessions. Concept tests of the solar system were conducted before and after lessons and analysis of covariance was conducted. The results of this study were as follows. First, science-based STEAM program using a portfolio was effective to form science concepts. Second, students opinion about science-based STEAM program using a portfolio was positive. Students think the program was effective in understanding science contents, promoting thinking, self-motivation. It is expected that this study will be basic material to expand STEAM in science education.

• Journal of the Korean Home Economics Association
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• v.31 no.3
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• pp.47-62
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• 1993

The purpose of the study were to: (1) determine important home management concepts in the secondary home economics education curriculum, (2) identify the educational needs related to home management perceived by students, home economics teachers, and university professors, (3) identify the factor structure of the home management concepts, (4) use the findings to make recommendations for defining the area of home management in the secondary home economics curriculum. Three versions of the questionnaire were used to assess the needs. One questionnaire was for students, one for home economics teachers, and one for professors. A total of 1,029 students, 385 home economics teachers, and 45 professors responded to the questionnaires. the data were analyzed by using the descriptive statistics, one way ANOVA with scheff -test, and factor analysis. Forty home management concepts were selected based on the related literatures. The respondants perceived these important for the secondary home economics curriculum. However, 36 home management concepts had differences in perceived importance among students, teachers, and professors. Nine factors emerged from the factor analysis. The three factors that were judged of most importance by students were communication and stress management, making money and helping household tasks, and leisure time activities. The professors and teachers perceived decision making and management process and knowing and utilizing resources most important.

• Journal of The Korean Association For Science Education
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• v.28 no.5
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• pp.424-437
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• 2008

In this study, we collected teachers' opinions with regard to the effects of the instruction using analogy generation, the disadvantages of the instruction, the problem-solving methods of the instruction, and the teacher's role in it, and accordingly tried to investigate its effectiveness with the analysis of students' academic achievements and motivation, and through the student's interview, after applying the activities of creating generated analogies, finding the difference between the objects and comparisons, and presenting new-known genetics concepts as the students themselves generated analogies. As a result of a teachers' workshop on instruction using analogy development, it was expected to have a positive effect on students' understanding of scientific concepts in genetics, which were found to be difficult for students to understand in learning biology. Students found analogy examples for concepts in genetics in daily life, compared their analogs to those of peers, and examined inconsistencies between targets and analogs through the process of discussion, which finally led to their correct perception of scientific concepts in genetics. In addition, instruction using student-generated analogies proved to have a more positive effect on improving academic achievement and motivating learning, compared with traditional expository instruction.

• Journal of the Korean Chemical Society
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• v.62 no.3
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• pp.243-252
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• 2018

In this study, we compared 8th graders' macroscopic and microscopic conceptions related to the properties of substances. A test for the basic particle concept and a test for the macroscopic and microscopic concepts of melting point, solubility, and density were developed and administered to 371 students. Their responses were classified into 4 categories on the bases of their understanding of the macroscopic and microscopic concepts. The proportions and characteristics of each category were also analyzed. The analyses of the results revealed that the students who understood the macroscopic concepts had various misconceptions at the microscopic level. Many students had difficulty in understanding not only microscopic concepts but macroscopic concepts. The microscopic responses of the students who did not understand the macroscopic concepts hardly corresponded with their macroscopic level responses. The students who responded correctly to the test for the basic particle concept also had difficulty in understanding the concept of the properties of substances. When they understood the macroscopic concepts, the proportions of the students who understood the microscopic concepts were high. On the bases of the results, educational implications for effective teaching and learning of concepts related to the properties of substances and for improving the future national curricular are discussed.

• Communications of Mathematical Education
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• v.22 no.3
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• pp.311-335
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• 2008

The importance of students' precise understanding of mathematical definitions, formulas, and theorems can not be underestimated. In this survey research, we attempted to evaluate students' understanding of the concepts of five topics -limit, continuity and intermediate theorem, derivative, application of derivative and integral. On the basis of the research result, this paper suggests that we need to 1) be more inventive and speculative in making test problems, 2) explain the examples and counter-examples more concretely, 3) stress and repeat the basic concepts on the stage of introducing new concepts, 4) develop more effective problems for the measure of students' understanding of mathematical concepts, 5) use developed problems in actual teaching.

• The Mathematical Education
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• v.45 no.3 s.114
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• pp.319-343
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• 2006

The purpose of this study is to investigate how fifth and sixth graders recognize average and to find out suggestions for teaching/learning methods of average by examining which difference there is depending on the way of the word problem presentation. For the this purpose, was conducted experiment study with the way of the world problem presentation set up as experimental treatment. The conclusions drawn from the results obtained in the this study were as follows : First, since students who did not learn the regular course of average had various informal concepts already, it is needed to consider handling more various concepts of average in order to enable students to expand flexible thoughts. Second, compared with fifth and sixth graders showed a wide difference in informal concepts of average depending on the way of the word problem presentation. In expect data with given average, concepts of mean as algorithm, balance point, and mode indicated similar percentage, while in estimate average with given data, the percentage of students who showed the concept of mean was very high at 67.6%. That may be because problems related to mean in the current textbooks are items of 'estimate average with given data', so in types of 'estimate average with given data', students solve questions with mean as algorithm without considering situations of problems. This result suggests that it is necessary to diversify the way of the word problem presentation even in textbooks. Third, as a result of analyzing informal concepts of average, there was significant difference in grades. In addition, the results suggested that there would be difference in the concepts of average depending on gender or attributes of discrete quantity and continuous quantity.