The Use of Video Demonstrations and Particulate Animation in General Chemistry

Different visualization techniques have been used for teaching chemistry concepts. Previous studies have shown that when molecular animations and video demonstrations are used, students seem to better correlate all three levels of representation: macroscopic, submicroscopic, and symbolic. This thinking process allows the students to improve their conceptual understanding and ability to create dynamic mental models. In this study, general chemistry students viewed three experiments involving dynamic fluid equilibrium in a graphic design, a video demonstration, and a molecular animation. The study investigated whether video demonstrations or particulate animations helped the students' conceptual understanding, and if the order of visualizations (video or animation first) produced any differences. Students showed improvement after each visualization. Surprisingly, there was significant improvement in responses between the first and second visualization. This work shows the importance of combining both types of visualizations, but it does not indicate a preference toward a specific order.     

Exploring How Different Features of Animations of Sodium Chloride Dissolution Affect Students’ Explanations

Animations of molecular structure and dynamics are often used to help students understand the abstract ideas of chemistry. This qualitative study investigated how the features of two different styles of molecular-level animation affected students’ explanations of how sodium chloride dissolves in water. In small group sessions 18 college-level general chemistry students dissolved table salt in water, after which they individually viewed two animations of salt dissolution. Before and after viewing each animation the participants provided pictorial, written, and oral explanations of the process at the macroscopic and molecular levels. The students then discussed the animations as a group. An analysis of the data showed that students incorporated some of the microscopic structural and functional features from the animations into their explanations. However, oral explanations revealed that in many cases, participants who drew or wrote correct explanations did not comprehend their meanings. Students’ drawings may have reflected only what they had seen, rather than a cohesive understanding. Students’ explanations given after viewing the animations improved, but some prior misconceptions were retained and in some cases, new misconceptions appeared. Students reported that they found the animations useful in learning; however, they sometimes missed essential features when they watched the animation alone.     

Correct Interpretation of Chemical Diagrams Requires Transforming from One Level of Representation to Another

Volunteer non-major chemistry students taking an introductory university chemistry course (n = 17) were interviewed about their understanding of a variety of chemical diagrams. All the students’ interviewed appreciated that diagrams of laboratory equipment were useful to show how to set up laboratory equipment. However students’ ability to explain specific diagrams at either the macroscopic or sub-microscopic level varied greatly. The results highlighted the poor level of understanding that some students had even after completing both exercises and experiments using the diagrams. The connection between the diagrams of the macroscopic level (equipment, chemicals), the sub-microscopic level (molecular) and the symbolic level (equations) was not always considered explicitly by students. The results indicate a need for chemical diagrams to be used carefully and more explicitly to ensure learner understanding. Correspondingly, students need to interpret visual chemical diagrams using meta-visualization skills linking the various levels of representation, and appreciating the role of the diagrams in explanations need to be developed.     

How are the Concepts and Theories of Acid–Base Reactions Presented? Chemistry in Textbooks and as Presented by Teachers

This paper investigates the views of science and scientific activity that can be found in chemistry textbooks and heard from teachers when acid–base reactions are introduced to grade 12 and university chemistry students. First, the main macroscopic and microscopic conceptual models are developed. Second, we attempt to show how the existence of views of science in textbooks and of chemistry teachers contributes to an impoverished image of chemistry. A varied design has been elaborated to analyse some epistemological deficiencies in teaching acid–base reactions. Textbooks have been analysed and teachers have been interviewed. The results obtained show that the teaching process does not emphasize the macroscopic presentation of acids and bases. Macroscopic and microscopic conceptual models involved in the explanation of acid–base processes are mixed in textbooks and by teachers. Furthermore, the non‐problematic introduction of concepts, such as the hydrolysis concept, and the linear, cumulative view of acid–base theories (Arrhenius and Brönsted) were detected.     

Effect of a labratory manual design incorporating visual information-processing aids on student learning and attitudes

The elements of visual information-processing theory were applied to the design of a chemistry laboratory manual. The effectiveness of this approach on content learning, practical skill mastery, and attitudes of university students in a general chemistry course was assessed. Two versions of a laboratory manual were developed: an experimental version that promotes visual information processing by integrating pictures or diagrams with text, and a control version identical to the experimental version in both activities and structure, but without pictures or diagrams. Three assessment instruments were used: an achievement test to assess cognitive outcomes, an attitude survey to assess affective outcomes, and a manipulative skills observation checklist to assess psychomotor outcomes. Results showed that the manual incorporating visual information-processing characteristics helped students gain significantly higher scores on measures of achievement and psychomotor skills, and also stimulated students to develop more favorable attitudes toward the laboratory activities. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 891–904, 1997.     

Integrating Model-Based Learning and Animations for Enhancing Students’ Understanding of Proteins Structure and Function

This paper describes a study conducted in the context of chemistry education reforms in Israel. The study examined a new biochemistry learning unit that was developed to promote in-depth understanding of 3D structures and functions of proteins and nucleic acids. Our goal was to examine whether, and to what extent teaching and learning via model-based learning and animations of biomolecules affect students’ chemical understanding. Applying the mixed methods research paradigm, pre- and post-questionnaires as well as class-observations were employed in the collection, analysis, and interpretation of data. The research population included 175 grade twelve students, divided into three research groups: (a) hands-on exploration of animations, (b) teacher’s demonstrations of animations, (c) traditional learning using textbooks. Findings indicated that the integration of model-based learning and 3D animations enhanced students’ understanding of proteins’ structure and function and their ability to transfer across different levels of chemistry understanding. Findings also indicated that teachers’ demonstrations of animations may enhance students’ ‘knowledge’—a low order thinking skill; however, in order to enhance higher levels of thinking, students should be able to explore 3D animations on their own. Applying constructivist and interpretative analysis of the data, three themes were raised, corresponding to cognitive, affective, and social aspects of learning while exploring web-based models and animations.     

Eliciting Metacognitive Experiences and Reflection in a Year 11 Chemistry Classroom: An Activity Theory Perspective

Concerns regarding students’ learning and reasoning in chemistry classrooms are well documented. Students’ reasoning in chemistry should be characterized by conscious consideration of chemical phenomenon from laboratory work at macroscopic, molecular/sub-micro and symbolic levels. Further, students should develop metacognition in relation to such ways of reasoning about chemistry phenomena. Classroom change eliciting metacognitive experiences and metacognitive reflection is necessary to shift entrenched views of teaching and learning in students. In this study, Activity Theory is used as the framework for interpreting changes to the rules/customs and tools of the activity systems of two different classes of students taught by the same teacher, Frances, who was teaching chemical equilibrium to those classes in consecutive years. An interpretive methodology involving multiple data sources was employed. Frances explicitly changed her pedagogy in the second year to direct students attention to increasingly consider chemical phenomena at the molecular/sub-micro level. Additionally, she asked students not to use the textbook until toward the end of the equilibrium unit and sought to engage them in using their prior knowledge of chemistry to understand their observations from experiments. Frances’ changed pedagogy elicited metacognitive experiences and reflection in students and challenged them to reconsider their metacognitive beliefs about learning chemistry and how it might be achieved. While teacher change is essential for science education reform, students are not passive players in change efforts and they need to be convinced of the viability of teacher pedagogical change in the context of their goals, intentions, and beliefs.     

The nature and extent of analogies in secondary chemistry textbooks

This paper describes an analogy classification framework used with high school chemistry textbooks. The framework takes into account aspects of past research into analogies in science education to allow for a systematic classification of textbook analogies based upon nine criteria including chemistry content area. Many of the 93 analogies classified described abstract chemistry concepts such as atomic structure and bonding, however, the frequent use of simple analogies, and the scarcity of stated limitations, are likely to create learning problems for students. In some textbooks, authors made use of margin spaces to include more analogies and these marginalised analogies often contained a pictorial component. Recommendations for further research into analogies in science education and possible methodological approaches are suggested.     

高中生使用化学教辅图书现状的调查研究

笔者利用自行设计的"高中生化学同步类化学教辅图书使用情况调查问卷",对北京市高中生使用化学教辅图书的现状进行了调查。研究结果表明:教辅图书与学生的化学学习有着紧密的联系,在化学学习的各个环节,学习各类化学知识,都有学生使用教辅图书,并且学生普遍认为化学教辅图书对"三维目标"尤其是"知识与技能"目标的实现的确起到了一定的积极作用;教科书自身的特征使其在知识点与习题方面不能满足大多数学生的需求,为教辅图书提供了立足之地;教师对学生选择及使用教辅图书有着重要的影响,但教师在这方面给予学生的指导有待进一步提高。     

Use of Animation in Teaching Cell Biology

To address the different learning styles of students, and because students can access animation from off-campus computers, the use of digital animation in teaching cell biology has become increasingly popular. Sample processes from cell biology that are more clearly presented in animation than in static illustrations are identified. The value of animation is evaluated on whether the process being taught involves motion, cellular location, or sequential order of numerous events. Computer programs for developing animation and animations associated with cell biology textbooks are reviewed, and links to specific examples of animation are given. Finally, future teaching tools for all fields of biology will increasingly benefit from an expansion of animation to the use of simulation. One purpose of this review is to encourage the widespread use of animations in biology teaching by discussing the nature of digital animation.     

Science Education in Primary Schools: Is an Animation Worth a Thousand Pictures?

Science teaching deals with abstract concepts and processes that very often cannot be seen or touched. The development of Java, Flash, and other web-based applications allow teachers and educators to present complex animations that attractively illustrate scientific phenomena. Our study evaluated the integration of web-based animated movies into primary schools science curriculum. Our goal was to examine teachers’ methods for integrating animated movies and their views about the role of animations in enhancing young students’ thinking skills. We also aimed at investigating the effect of animated movies on students’ learning outcomes. Applying qualitative and quantitative tools, we conducted informal discussions with science teachers (N = 15) and administered pre- and post-questionnaires to 4th (N = 641) and 5th (N = 694) grade students who were divided into control and experimental groups. The experimental group students studied science while using animated movies and supplementary activities at least once a week. The control group students used only textbooks and still-pictures for learning science. Findings indicated that animated movies support the use of diverse teaching strategies and learning methods, and can promote various thinking skills among students. Findings also indicated that animations can enhance scientific curiosity, the acquisition of scientific language, and fostering scientific thinking. These encouraging results can be explained by the fact that the students made use of both visual-pictorial and auditory-verbal capabilities while exploring animated movies in diverse learning styles and teaching strategies.     

Enabling, facilitating, and inhibiting effects of animations in multimedia learning: Why reduction of cognitive load can have negative results on learning

New technologies allow the display of text, static visuals, and animations. Although animations are inherently attractive, they are not always beneficial for learning. Problems may arise especially when animations modify the learner's cognitive load in an unintended way. In two learning experiments with 40 and 26 university students, the effects of animated pictures on knowledge acquisition were investigated. Some pictures displayed visual simulations of changes over time, whereas other pictures could be manipulated by learners to represent different states in time. Results showed that manipulation pictures had an enabling function for individuals with high learning prerequisites, whereas simulation pictures had a facilitating function for individuals with low learning prerequisites. However, the facilitating function was not beneficial for learning, because learners were prevented from performing relevant cognitive processes on their own. A careful analysis of the interrelation between different kinds of cognitive load and the process of learning is therefore required.     

Classification of chemical reactions: Stages of expertise

In this study we explore the strategies that undergraduate and graduate chemistry students use when engaged in classification tasks involving symbolic and microscopic (particulate) representations of different chemical reactions. We were specifically interested in characterizing the basic features to which students pay attention when classifying chemical reactions at the symbolic and microscopic levels. We identified the categories that students create when classifying chemical reactions, and compared the performance in simple classification tasks of students with different levels of preparation in the discipline. Our results suggest that advanced levels of expertise in chemical classification do not necessarily evolve in a linear and continuous way with academic training; a significant proportion of undergraduate students, regardless of their level of preparation in chemistry, based their classification schemes on the identification of surface features and failed to create chemically meaningful classes. Students' ability to identify chemically meaningful groups was strongly influenced by their recent learning experiences and their graduate work in chemistry. The level of expertise and the type of chemical representation influenced the number and types of categories created, the nature of the features used to build a class, and the role that these features played during the classification process. Although all of the participants in our study expressed similar levels of unfamiliarity with the microscopic images of chemical reactions, advanced students were more adept at using the available representational features to build chemical meaning. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 45: 771–793, 2008     

When learning from animations is more successful than learning from static pictures: learning the specifics of change

The results of three meta-analyses show that the effectiveness of learning from animations, when compared to learning from static pictures, is rather limited. A recent re-analysis of one of these meta-analyses, however, supports that learning from animations is considerably more effective than learning from static pictures if the specifics of the displayed changes need to be learned. In order to further validate this finding as well as to clarify the educational strengths and weaknesses of animations and static pictures, an experimental study with three groups was conducted. Overall, 88 university students participated in the study. One group of learners (n?=?30) watched a single picture of a gear mechanism, one group of learners (n?=?28) watched four pictures, and one group of learners (n?=?30) watched an animation. All groups had to identify specific motions and spatial arrangements covered by the gear mechanism. While learners who watched the animation exhibited the best performance with respect to the identification of motions, learners who watched the pictures showed the best performance with respect to the identification of spatial arrangements. The effect sizes are large. The results of the study help to clarify when animations and when static pictures are most suitable for learning.

     

A quantitative analysis of high school chemistry textbooks for scientific literacy themes and expository learning aids

The purpose of this study was to examine the content of seven high school chemistry textbooks for curriculum balance and emphasis on the following aspects of scientific literacy: (a) science as a body of knowledge, (b) science as a way of investigating, (c) science as a way of thinking, and (d) the interaction among science, technology, and society. In addition, the number of textbook pages, vocabulary terms, pictures, questions, and problems at the end of the chapter were determined. The textbook is an important teaching aid in high school chemistry courses, which conveys some of the information that students receive and influences how students perceive this subject. The majority of chemistry textbooks we analyzed stress science as a body of knowledge, place some emphasis on science as a way of investigating, have practically eliminated science as a way of thinking, and devote very little text to the interaction among science, technology, and society. Furthermore, these are voluminous books that range in length from 466 to 729 pages, with as many as 60 questions per chapter.     

Analogies in chemistry textbooks

Abstract

This study combines a critical analysis of analogies found in eight chemistry textbooks used by Australian senior high school students with the views of the textbook authors about analogies in chemistry textbooks and teaching. Sixty‐two analogies were identified which described abstract chemical concepts such as atomic structure and collision theory. A range of styles, including pictorial analogies, were identified and the analogies were found to have variant amounts of analogical mapping and analogue explanation. Analogical limitations were rarely identified. Authors contended that they were cautious about including analogies in textbooks as analogies require a flexibility not available when they are set in print. It was argued that analogy was best applied as a strategy for teachers in response to them perceiving that students had misunderstood an original explanation.     

Analysis of activities included in Saudi Arabian chemistry textbooks for the inclusion of argumentation-driven inquiry skills

This research aimed to determine the extent to which twelfth-grade chemistry textbooks and workbooks included argumentation-driven inquiry skills in their activities. For this purpose, all activities found in the twelfth grade chemistry textbooks and workbooks were analyzed using an analysis rubric. Results indicate that the inclusion of the argumentation-driven inquiry skills in the analyzed chemistry activities generally fell within argumentation-driven inquiry levels one and two. This type of inclusion favors teacher-centered learning and teaching rather than student-centered learning and teaching. Therefore, the authors recommend that these textbooks and workbooks be revised to ensure that the argumentation-driven inquiry skills that are included are directed toward student-centered learning and teaching as required by levels four and three.