Effects of ‘Environmental Chemistry’ Elective Course Via Technology-Embedded Scientific Inquiry Model on Some Variables

The purpose of this study is to examine the effects of ‘environmental chemistry’ elective course via Technology-Embedded Scientific Inquiry (TESI) model on senior science student teachers’ (SSSTs) conceptions of environmental chemistry concepts/issues, attitudes toward chemistry, and technological pedagogical content knowledge (TPACK) levels. Within one group pre-test–post-test design, the study was conducted with 117 SSSTs (68 females and 49 males—aged 21–23 years) enrolled in an ‘environmental chemistry’ elective course in the spring semester of 2011–2012 academic-years. Instruments for data collection comprised of Environmental Chemistry Conceptual Understanding Questionnaire, TPACK survey, and Chemistry Attitudes and Experiences Questionnaire. Significant increases in the SSSTs’ conceptions of environmental chemistry concepts/issues, attitudes toward chemistry, and TPACK levels are attributed to the SSSTs learning how to use the innovative technologies in the contexts of the ‘environmental chemistry’ elective course and teaching practicum. The study implies that the TESI model may serve a useful purpose in experimental science courses that use the innovative technologies. However, to generalize feasibility of the TESI model, it should be evaluated with SSSTs in diverse learning contexts.     

STUDENTS’ CONCEPTIONS OF THE PARTICULATE NATURE OF MATTER AT SECONDARY AND TERTIARY LEVEL

The aim of the present study is to elicit students’ understanding of the particulate nature of matter via a cross-age study ranging from secondary to tertiary educational levels. A questionnaire with five-item open-ended questions was administered to 166 students from the secondary to tertiary levels of education. In light of the findings, it can be deduced that the number of students’ responses categorized under the “sound understanding” category for each item increased with educational level, except for U1. Also, it can be concluded that students’ specific misconceptions decreased steadily from SHS1 to SHS3, except for item 4, but there is surprisingly a clear increase at U1.     

A Thematic Review of Studies into the Effectiveness of Context-Based Chemistry Curricula

Context-based chemistry education aims at making connections between real life and the scientific content of chemistry courses. The purpose of this study was to evaluate context-based chemistry studies. In looking for the context-based chemistry studies, the authors entered the keywords ??context-based??, ??contextual learning?? and ??chemistry education?? in well-known databases (i.e. Academic Search Complete, Education Research Complete, ERIC, Springer LINK Contemporary). Further, in case the computer search by key words may have missed a rather substantial part of the important literature in the area, the authors also conducted a hand search of the related journals. To present a detailed thematic review of context-based chemistry studies, a matrix was used to summarize the findings by focusing on insights derived from the related studies. The matrix incorporates the following themes: needs, aims, methodologies, general knowledge claims, and implications for teaching and learning, implications for curriculum development and suggestions for future research. The general knowledge claims investigated in this paper were: (a) positive effects of the context-based chemistry studies; (b) caveats, both are examined in terms of students?? attitudes and students?? understanding/cognition. Implications were investigated for practice in context-based chemistry studies, for future research in context-based chemistry studies, and for curriculum developers in context-based chemistry studies. Teachers of context-based courses claimed that the application of the context-based learning approach in chemistry education improved students?? motivation and interest in the subject. This seems to have generated an increase in the number of the students who wish to continue chemistry education at higher levels. However, despite the fact that the majority of the studies have reported advantages of context-based chemistry studies, some of them have also referred to pitfalls, i.e. dominant structure of out-of-school learning, tough nature of some chemistry topics, and teacher anxiety of lower-ability students.     

Analogical reasoning for understanding solution rates: students’ conceptual change and chemical explanations

The study aims to demonstrate evidence of (a) students’ conceptual change on solution rates; (b) students’ sub‐microscopic explanations of dissolution; and (c) retention of the concepts of solution rates. The sample consists of 44 Grade 9 students (18 boys and 26 girls) drawn purposively from two different classes (22 each) in the city of Trabzon, Turkey. The current study incorporates multiple methods of data collection: items from a solution concept test, clinical interviews and examination of students’ self‐assessment tasks. The results reveal that there is a statistically significant difference between scores in pre‐test and post‐test and between pre‐test and delayed test (p < 0.05). This research indicates that the intervention has improved students’ understanding of the conceptual relationship between solution rates and the sub‐microscopic explanation of dissolution. It has also helped in overcoming students’ alternative conceptions to some extent. However, alternative conceptions have not been eliminated completely. In the light of the results, this current study suggests that a simple model such as the four‐step constructivist teaching (4E) is efficient.     

Reducing the demand uncertainties at the fuzzy-front-end of developing new online services

Addressing the demand uncertainties at the fuzzy-front-end of developing new online services, this paper tests the roles of numerous cluster-based methodologies in improving the predictive accuracy of consumer opinions. The results with an online service revealed that both crisp and non-crisp clustering methodologies improve the predictive accuracy and hence reduce the demand uncertainties at the fuzzy-front-end of the new product development process. They also showed that non-crisp clustering increases the accuracy more than does crisp clustering. Implications of the findings for our understanding of the earlier stages of the new product development process and for making informed R&D policies are discussed.     

A Comparison of Different Conceptual Change Pedagogies Employed Within the Topic of “Sound Propagation”

The purpose of this study was to compare different conceptual change methods within a topic on ‘sound propagation’. The study was conducted with 80 grade 5 students (aged 11–12 year old) drawn from four cohort classes in an elementary school on the north coast of Black Sea Region in Turkey. While one class was assigned as a control group, the others formed experimental groups (one with a conceptual change text, one with analogies presented as computer animations and one with a combination of conceptual change text, analogies and computer animations). A questionnaire with 10 two-tier questions was administered as a pretest a week before the teaching intervention, and the same test was re-administered immediately after the intervention as a post-test. The questionnaire was also employed as a delayed post-test 3 weeks after the teaching intervention. The experimental groups performed significantly better in the post-test that the control group (p < 0.05). Within the experimental groups, the group exposed to a combination of the conceptual change text, analogies and computer animations performed best on the post-test and the delayed post-test (p < 0.05). Overall the study indicated that the intervention that employed the entire suite of conceptual change pedagogies produced the best learning outcomes.     

Investigating the Effectiveness of a Constructivist-based Teaching Model on Student Understanding of the Dissolution of Gases in Liquids

The research presented in this paper consisted of an investigation of the effectiveness of a four-step constructivist-based teaching activity on student understanding of how pressure and temperature influence the dissolution of a gas in a liquid. Some 44 Grade 9 students (18 boys and 26 girls) selected purposively from two school classes in the city of Trabzon, Turkey participated in the study. Students’ understanding were evaluated from examination of two items from a purpose-designed solution concept test, face-to-face semi-structured interviews and examination of students’ self-assessment exercises. Statistical analysis using two-way ANOVA of student test scores point to statistically-significant differences in test and total scores (p < 0.05) suggesting that the teaching activities employed help students achieve better conceptual understanding. Further, no statistically significant differences were seen between post-test and delayed test scores, suggesting that teaching the activities enable students to retain their new conceptions in their long-term memory. However, in a few instances the activities resulted in the development of new alternative conceptions, suggesting teachers need to be conscious of the positive and negative effects of any teaching intervention.     

Facilitating Conceptual Change in Students’ Understanding of Boiling Concept

The objective of this study was to construct a teaching strategy for facilitating students’ conceptual understanding of the boiling concept. The study is based on 52 freshman students in the primary science education department. Students’ ideas were elicited by a test consisting of nine questions. Conceptual change strategy was designed based on students’ alternative conceptions. Conceptual change in students’ understanding of boiling was evaluated by administering a pre-, post- and delayed post-test. The test scores were analysed both by qualitative and quantitative methods. Statistical analysis using one-way ANOVA of student test scores pointed to statistically significant differences in the tests and total scores (p < 0.05). Quantitative analysis of students’ responses on each test revealed different schema about changing their knowledge system. Both qualitative and quantitative analyses suggest that the teaching activities facilitated students’ conceptual understanding. No statistically significant differences were found between post-test and delayed post-test scores, suggesting that the teaching strategy enabled students to retain their new conceptions in the long-term memory.     

A comparison of level of understanding of eighth‐grade students and science student teachers related to selected chemistry concepts

The aim of this study is to investigate and compare level of understanding of eighth‐grade students and student teachers in their final year in the science education department related to concepts of solution, gas, and chemical change. A qualitative and quantitative methodology was used for this investigation. Open‐ended questions and group discussion methods were used for data collection. Moreover, to examine how students visualize these concepts, students were asked to make drawings. The questions were administered to 50 students in Grade 8 and 50 student teachers in the science education department. Group discussions were conducted with 6 students and 6 student teachers. There were surprisingly similar alternative conceptions by both the students and the student teachers despite more instruction on these topics in the education of the student teachers. Based on the results, some suggestions are presented. © 2005 Wiley Periodicals, Inc. J Res Sci Teach     

The Effect of Conceptual Change Pedagogy on Students’ Conceptions of Rate of Reaction

This paper reports on an investigation of the effect of conceptual change pedagogy on students’ conceptions of ‘rate of reaction’ concepts. The study used a pre-test/post-test non-equivalent comparison group design approach and the sample consisted of 72 Turkish grade-11 students (aged 16–18 years) selected from two intact classrooms. The ‘Rate of Reaction’ Concept Test comprising 9 lead and 10 sub-questions (total 19 items) was employed. The results suggest that the teaching intervention helped the students to overcome their alternative conceptions and to store their newly structured knowledge in their long-term memories. It is suggested that combining different conceptual change methods such conceptual change text/refutation text, argumentation with the intervention used here may be more effective in reducing student alternative conceptions.