A Macro–Micro–Symbolic Teaching to Promote Relational Understanding of Chemical Reactions

The purpose of this research is threefold: (1) to identify the difficulties that Grade 10 students in a Lebanese school have that hinder their conceptual understanding at the micro–macro–symbolic interface in chemistry, (2) to investigate the effect of a macro–micro–symbolic teaching approach on students’ relational understanding of chemical reactions, and (3) to characterize students’ conceptual profiles regarding their understanding of chemical reactions in terms of macro, micro, symbolic levels and the relations among them, at the end of the teaching sequence. Forty six 10th graders from two sections participated in the study. A student-centered approach was followed in both sections based on constructivist pedagogy. Hence the teacher played the role of a facilitator who guided students in a meaning making inductive learning process, through questioning, monitoring, validating, and clarifying ideas. Instruction in the experimental group was characterized by macro–micro–symbolic teaching that focuses on the interplay between the levels, integrates various representations, and engages students in an epistemic discourse about the nature of knowing in chemistry. Data sources for the study included a pre-test and two post-intervention tasks: a post-test and a concept map task, in addition to interviews with selected students from both sections. Findings indicated that macro–micro–symbolic teaching enhanced students’ conceptual understanding and relational learning of chemical reactions. Besides, four assertions related to students’ conceptual and epistemological thinking in response to the different teaching approaches are presented. Implications for instruction and for teacher education programs, as well as recommendations for further research, are discussed in light of these findings.     

Different ways in which students handle chance encounters in the explorative setting of a dice game

The purpose of this study is to investigate the ways in which Swedish seventh grade students (12 and 13 years old) handle chance encounters. Four groups of students working in pairs participated in the study. In the group discussions, which were tape-recorded and fully transcribed, the students were encouraged to explore strategies for winning a specifically designed dice game based on the sum of two dice. The dice game included four different set-ups of dice designed to bring to the fore different aspects of probability modelling and to offer the student the opportunity to encounter small differences in the mathematical structure of the sample space and of the probability distribution between the four different set-ups. The study describes strategies that the students use when confronted with these different set-ups, what their activities imply in terms of resources in handling random phenomena and what the dice game offers in terms of opportunities for learning probability. In order to explain such meaning-making processes the students’ activities are viewed from a perspective that takes into consideration how the students’ understanding varies with their interpretations of the situation they are confronted with, i.e., how they contextualize the different set-ups of the dice game. The results show how the students, during the course of the game, reorganize their interpretations of the mathematical content confronting them, and how a variation of guiding principles becomes the object of exploration. Approaches of extremes and a number model are described as a means for the students to identify and assign probabilities for the total of two dice.     

An inquiry-based augmented reality mobile learning approach to fostering primary school students’ historical reasoning in non-formal settings

This study investigated the contribution of a location-based augmented reality (AR) inquiry-learning environment in developing 3rd grade students’ historical empathy and conceptual understanding. Historical empathy is an important element of historical thinking, which is considered to improve conceptual understanding and support the development of democratic citizens by helping students interpret, understand and connect patterns of human activity across time. Fifty-three 3rd grade students, grouped in two research conditions, participated in this study. Students visited an archaeological site with and without the support of an AR learning environment on mobile tablet devices. Data from all students were collected following a pre- and post-test design. Twelve students from the AR condition participated in individual interviews and all AR students took a delayed post-test. The results showed that students’ conceptual understanding and historical empathy increased from pre to post for both conditions. Statistically significant differences were found between the AR field trip and the traditional field trip students in the development of empathy and conceptual understanding. These results add to the literature by supporting the potential of AR technologies for the development of students’ historical empathy; several design implications are also discussed.     

Multiple Representation in Learning About Evaporation

There has been extensive research on children’s understanding of evaporation, but representational issues entailed in this understanding have not been investigated in depth. This study explored three students’ engagement with science concepts relating to evaporation through various representational modes, such as diagrams, verbal accounts, gestures, and captioned drawings. This engagement entailed students (a) clarifying their thinking through exploring representational resources; (b) developing understanding of what these representations signify; and (c) learning how to construct representational aspects of scientific explanation. The study involved a sequence of classroom lessons on evaporation and structured interviews with nine children, and found that a focus on representational challenges provided fresh insights into the conceptual task involved in learning science. The findings suggest that teacher‐mediated negotiation of representational issues as students construct different modal accounts can support enriched learning by enabling both (a) richer conceptual understanding by students; and (b) enhanced teacher insights into students’ thinking.     

The Virtual Solar System Project: Developing Conceptual Understanding of Astronomical Concepts Through Building Three-Dimensional Computational Models

The Virtual Solar System (VSS) course described in this paper is one of the first attempts to integrate three-dimensional (3D) computer modeling as a central component of an introductory undergraduate astronomy course. Specifically, this study assessed the changes in undergraduate university students' understanding of astronomy concepts as a result of participating in an experimental introductory astronomy course in which the students constructed 3D models of different astronomical phenomena. In this study, we examined students' conceptual understanding concerning three foundational astronomical phenomena: the causes of lunar and solar eclipses, the causes of the Moon's phases, and the reasons for the Earth's seasons. Student interviews conducted prior to the course identified a range of student alternative conceptions previously identified in the literature regarding the dynamics and mechanics of the Solar System. A previously undocumented alternative conception to explain lunar eclipses is identified in this paper. The interviews were repeated at the end of the course in order to quantitatively and qualitatively assess any changes in student conceptual understanding. Generally, the results of this study revealed that 3D computer modeling can be a powerful tool in supporting student conceptualization of abstract scientific phenomena. Specifically, 3D computer modeling afforded students the ability to visualize abstract 3D concepts such as the line of nodes and transform them into conceptual tools, which in turn, supported the development of scientifically sophisticated conceptual understandings of many basic astronomical topics. However, there were instances where students' conceptual understanding was incomplete and frequently hybridized with their existing conceptions. These findings have significant bearing on when and in what domains 3D computer modeling can be used to support student conceptual understanding of astronomy concepts.     

Effect of the 5E Model on Prospective Teachers’ Conceptual Understanding of Diffusion and Osmosis: A Mixed Method Approach

The aim of this study was to explore a group of prospective primary teachers’ conceptual understanding of diffusion and osmosis as they implemented a 5E constructivist model and related materials in a science methods course. Fifty prospective primary teachers’ ideas were elicited using a pre- and post-test and delayed post-test survey consisting of ten two-tier questions of which an explanatory part was integral. Individual interviews were conducted with six prospective teachers at the end of the implementation of the unit using four questions. Test scores were analyzed quantitatively and qualitatively. Post-instructional interviews were analyzed qualitatively. Statistical analysis using one-way ANOVA of student test scores pointed to statistically significant differences between pre- and post- and delayed post-test (p < 0.05). A qualitative analysis of the prospective teachers’ explanations in the two-tier questions revealed changes in their ideas overtime. Both quantitative and qualitative analyses suggest that the teaching activities promoted students’ conceptual understanding. No statistically significant differences were found between post-test and delayed post-test scores, suggesting that the teaching activities based on 5E model enabled students to retain their new conceptual understanding.     

The effect of a conceptual change approach on understanding of students’ chemical equilibrium concepts

The purpose of this study was to compare the effects of a conceptual change approach over traditional instruction on tenth‐grade students’ conceptual achievement in understanding chemical equilibrium. The study was conducted in two classes of the same teacher with participation of a total of 44 tenth‐grade students. In this study, a pre‐test/post‐test control group semi‐experimental design pattern was used. During teaching the topic of chemical equilibrium concepts in the chemistry curriculum, a conceptual change approach was applied in the experimental group whereas traditional instruction was followed in the control group. Data were analysed with an independent samples t‐test, and an analysis of covariance using the pre‐test scores as the covariate. The results showed that the conceptual change approach was statistically more effective than traditional instruction in terms of students’ conceptual understanding. After the six‐week intervention, interviews were conducted with 18 selected students in the study. In the interviews a prevailing alternative conception was detected beside many alternative conceptions. When they were asked to compare equilibrium constants of two different reactions they mostly responded to mean that ‘the bigger the mol number of the products, the bigger the equilibrium constant’ without considering what proportions the reactants were transformed into products in a reaction. Also, in this study a two‐tier multiple choice test was developed related to chemical equilibrium to detect students’ concepts and alternative concepts.     

Representational Issues in Students Learning About Evaporation

This study draws on recent research on the central role of representation in learning. While there has been considerable research on students’ understanding of evaporation, the representational issues entailed in this understanding have not been investigated in depth. The study explored students’ engagement with evaporation phenomena through various representational modes. The study indicates how a focus on representation can provide fresh insights into the conceptual task involved in learning science through an investigation of students’ responses to a structured classroom sequence and subsequent interviews over a year. A case study of one child’s learning demonstrates the way conceptual advances are integrally connected with the development of representational modes. The findings suggest that teacher-mediated negotiation of representational issues as students construct different modal accounts can support enriched learning by enabling both (a) richer conceptual understanding by students, and (b) enhanced teacher insights into students’ thinking.     

Using Writing-to-Learn Science Strategies to Improve Year 11 Students' Understandings of Stoichiometry

This study researched the use of writing-to-learn strategies within a high-school (Year 11) chemistry classroom. The writing task itself asked the students to write a business letter to a younger audience of middle-school (Year 7) students. A mixed-method design was used for the study, incorporating pre/post- testing with semi-structured interviews. The evidence supports that the treatment students performed statistically significantly better on a conceptual question compared to the control group. Additionally, the treatment students felt that writing to a younger audience prompted them to use different language than they would have if, for example, writing to their teacher. Further, the treatment students described that the writing task promoted their understanding of and their confidence in their knowledge of the stoichiometry concepts addressed in class.     

基于理解性任务的小数理解调查研究

为了解师生对小数的理解情况,研究开发了小数理解性任务,并对52名五年级学生和15名教师（6名职前,9名在职）进行了测试。结果表明:师生共运用了9种思维策略,其中“组成部分思维”与“等值思维”为两种主要策略;教师和学生的主要思维策略是一致的,教师的思维策略分布更复杂,但思维深度并不高于学生。9种思维策略可概念化为基于符号形式和基于符号意义两种思考路径。基于所建构的思维策略与思维路径,研究认为教学需对小数概念进行整合,建构多元理解下的小数概念整体:在宏观筹划上贯彻概念联系,在概念理解上聚焦概念结构,在概念发展中注重概念的双重性质。     

Chinese and Australian Year 3 Children's Conceptual Understanding of Science: A multiple comparative case study

Children have formal science instruction from kindergarten in Australia and from Year 3 in China. The purpose of this research was to explore the impact that different approaches to primary science curricula in China and Australia have on children's conceptual understanding of science. Participants were Year 3 children from three schools of high, medium and low socio-economic status in Hunan Province, central south China (n?=?135) and three schools of similar socio-economic status in Western Australia (n?=?120). The students' understanding was assessed by a science quiz, developed from past Trends in Mathematics and Science Study science released items for primary children. In-depth interviews were carried out to further explore children's conceptual understanding of living things, the Earth and floating and sinking. The results revealed that Year 3 children from schools of similar socio-economic status in the two countries had similar conceptual understandings of life science, earth science and physical science. Further, in both countries, the higher the socio-economic status of the school, the better the students performed on the science quiz and in interviews. Some idiosyncratic strengths and weaknesses were observed, for example, Chinese Year 3 children showed relative strength in classification of living things, and Australian Year 3 children demonstrated better understanding of floating and sinking, but children in both countries were weak in applying and reasoning with complex concepts in the domain of earth science. The results raise questions about the value of providing a science curriculum in early childhood if it does not make any difference to students' conceptual understanding of science.     

The Collaboration of Cooperative Learning and Conceptual Change: Enhancing the Students’ Understanding of Chemical Bonding Concepts

The main purpose of this study was to investigate the effects of cooperative learning based on conceptual change approach instruction on ninth-grade students’ understanding in chemical bonding concepts compared to traditional instruction. Seventy-two ninth-grade students from two intact chemistry classes taught by the same teacher in a public high school participated in the study. The classes were randomly assigned as the experimental and control group. The control group (N?=?35) was taught by traditional instruction while the experimental group (N?=?37) was taught cooperative learning based on conceptual change approach instruction. Chemical Bonding Concept Test (CBCT) was used as pre- and post-test to define students’ understanding of chemical bonding concepts. After treatment, students’ interviews were conducted to observe more information about their responses. Moreover, students from experimental groups were interviewed to obtain information about students’ perceptions on cooperative work experiences. The results from ANCOVA showed that cooperative learning based on conceptual change approach instruction led to better acquisition of scientific conceptions related to chemical bonding concepts than traditional instruction. Interview results demonstrated that the students in the experimental group had better understanding and fewer misconceptions in chemical bonding concepts than those in the control group. Moreover, interviews about treatment indicated that this treatment helped students’ learning and increased their learning motivation and their social skills.     

The Contribution of Conceptual Change Texts Accompanied by Concept Mapping to Eleventh-Grade Students Understanding of Cellular Respiration Concepts

The present study conducted to investigate the contribution of conceptual change texts, accompanied by concept mapping instruction to eleventh-grade students’ understanding of cellular respiration concepts, and their retention of this understanding. Cellular respiration concepts test was developed as a result of examination of related literature and interviews with teachers regarding their observations of students’ difficulties. The test was administrated as pre-test, post-test, and delayed post-test to a total of 70 eleventh-grade students in two classes of the same high school in an urban area, taught by the same teacher. The experimental group was a class of 34 students who received conceptual change texts accompanied by concept mapping instruction. A class of 36 students comprised the control group who received traditional instruction. Besides treatment, previous understanding and logical thinking ability were other independent variables involved in this study. The results showed that logical thinking, treatment, previous understanding of cellular respiration concepts each made a statistically significant contribution to the variation in students’ understanding of cellular respiration concepts. The result also showed that conceptual change texts accompanied by concept mapping instruction was significantly better than traditional instruction in retention of this understanding.     

Upper Secondary Students’ Understanding of the Use of Multiple Models in Biology Textbooks—The Importance of Conceptual Variation and Incommensurability

In this study we investigate students’ ability to discern conceptual variation and the use of multiple models in genetics when reading content-specific excerpts from biology textbooks. Using the history and philosophy of science as our reference, we were able to develop a research instrument allowing students themselves to investigate the occurrence of multiple models and conceptual variation in Swedish upper secondary textbooks. Two excerpts using different models of gene function were selected from authentic textbooks. Students were given the same questionnaire-instrument after reading the two texts, and the results were compared. In this way the students themselves made a classification of the texts which could then be compared with the researchers’ classification of the texts. Forty-one upper secondary students aged 18–19 participated in the study. Nine of the students also participated in semi-structured interviews. Students recognized the existence of multiple models in a general way, but had difficulty discerning the different models and the conceptual variation that occurs between them in the texts. Further they did not recognize the occurrence of incommensurability between multiple models. Students had difficulty in transforming their general knowledge of multiple models into an understanding of content specific models of gene function in the textbooks. These findings may have implications for students’ understanding of conceptual knowledge because research has established textbooks as one of the most influential aspects in the planning and execution of biology lessons, and teachers commonly assign reading passages to their students without further explanation.     

Using the Science Writing Heuristic Approach to Enhance Student Understanding in Chemical Change and Mixture

This study investigated the effect of the Science Writing Heuristic (SWH) approach on grade 9 students’ understanding of chemical change and mixture concepts. Four intact classes taught by two chemistry teachers from a Turkish public high school were selected for the study; one class was assigned as the treatment group, and the other class was assigned as the comparison group. Students in the treatment group were instructed by the SWH approach, while those in the comparison group were instructed with traditionally designed chemistry instruction. Tests measuring students’ conceptual understanding in the units of chemical change and mixture were administered as pre- and posttest for both groups. At the end of the instruction, semistructured interviews were conducted with 13 students from the treatment group and eight students from the comparison group. ANCOVA results revealed that the SWH approach was superior to the traditional approach on students’ understanding of chemical change and mixture concepts. Interview results indicated that students in the treatment group demonstrated better scientific understanding of chemical change and mixture concepts compared to those in the comparison group.     

Building the BIKE: Development and Testing of the Biotechnology Instrument for Knowledge Elicitation (BIKE)

Identifying students’ conceptual scientific understanding is difficult if the appropriate tools are not available for educators. Concept inventories have become a popular tool to assess student understanding; however, traditionally, they are multiple choice tests. International science education standard documents advocate that assessments should be reform based, contain diverse question types, and should align with instructional approaches. To date, no instrument of this type targeting student conceptions in biotechnology has been developed. We report here the development, testing, and validation of a 35-item Biotechnology Instrument for Knowledge Elicitation (BIKE) that includes a mix of question types. The BIKE was designed to elicit student thinking and a variety of conceptual understandings, as opposed to testing closed-ended responses. The design phase contained nine steps including a literature search for content, student interviews, a pilot test, as well as expert review. Data from 175 students over two semesters, including 16 student interviews and six expert reviewers (professors from six different institutions), were used to validate the instrument. Cronbach’s alpha on the pre/posttest was 0.664 and 0.668, respectively, indicating the BIKE has internal consistency. Cohen’s kappa for inter-rater reliability among the 6,525 total items was 0.684 indicating substantial agreement among scorers. Item analysis demonstrated that the items were challenging, there was discrimination among the individual items, and there was alignment with research-based design principles for construct validity. This study provides a reliable and valid conceptual understanding instrument in the understudied area of biotechnology.