Students’ Views of Scientific Models and Modeling: Do Representational Characteristics of Models and Students’ Educational Levels Matter?

The aim of this study was to examine the potential impact of the representational characteristics of models and students’ educational levels on students’ views of scientific models and modeling (VSMM). An online multimedia questionnaire was designed to address three major aspects of VSMM, namely the nature of models, the nature of modeling, and the purpose of models. The three scales of representational characteristics included modality, dimensionality, and dynamics. A total of 102 eighth graders and 87 eleventh graders were surveyed. Both quantitative data and written responses were analyzed. The influence of the representational characteristics seemed to be more salient on the nature of models and the purpose of models. Some interactions between the educational levels and the representational characteristics showed that the high school students were more likely to recognize textual representations and pictorial representations as models, while also being more likely to appreciate the differences between 2D and 3D models. However, some other differences between educational levels did not necessarily suggest that the high school students attained more sophisticated VSMM. For instance, in considering what information should be included in a model, students’ attention to particular affordances of the representation can lead to a more naive view of modeling. Implications for developing future questionnaires and for teaching modeling are suggested in this study.     

Diagnosing Students’ Understanding of the Nature of Models

Students’ understanding of models in science has been subject to a number of investigations. The instruments the researchers used are suitable for educational research but, due to their complexity, cannot be employed directly by teachers. This article presents forced choice (FC) tasks, which, assembled as a diagnostic instrument, are supposed to measure students’ understanding of the nature of models efficiently, while being sensitive enough to detect differences between individuals. In order to evaluate if the diagnostic instrument is suitable for its intended use, we propose an approach that complies with the demand to integrate students’ responses to the tasks into the validation process. Evidence for validity was gathered based on relations to other variables and on students’ response processes. Students’ understanding of the nature of models was assessed using three methods: FC tasks, open-ended tasks and interviews (N?=?448). Furthermore, concurrent think-aloud protocols (N?=?30) were performed. The results suggest that the method and the age of the students have an effect on their understanding of the nature of models. A good understanding of the FC tasks as well as a convergence in the findings across the three methods was documented for grades eleven and twelve. This indicates that teachers can use the diagnostic instrument for an efficient and, at the same time, valid diagnosis for this group. Finally, the findings of this article may provide a possible explanation for alternative findings from previous studies as a result of specific methods that were used.     

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.     

Introductory Biology Students’ Conceptual Models and Explanations of the Origin of Variation

Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess understanding of the origin of variation. By midterm, only a small percentage of students articulated complete and accurate representations of the origin of variation in their models. Targeted feedback was offered through activities requiring students to critically evaluate peers’ models. At semester''s end, a substantial proportion of students significantly improved their representation of how variation arises (though one-third still did not include mutation in their models). Students’ written explanations of the origin of variation were mostly consistent with their models, although less effective than models in conveying mechanistic reasoning. This study contributes evidence that articulating the genetic origin of variation is particularly challenging for learners and may require multiple cycles of instruction, assessment, and feedback. To support meaningful learning of the origin of variation, we advocate instruction that explicitly integrates multiple scales of biological organization, assessment that promotes and reveals mechanistic and causal reasoning, and practice with explanatory models with formative feedback.     

The Relation between Students’ Epistemological Understanding of Computer Models and their Cognitive Processing on a Modelling Task

While many researchers in science education have argued that students’ epistemological understanding of models and of modelling processes would influence their cognitive processing on a modelling task, there has been little direct evidence for such an effect. Therefore, this study aimed to investigate the relation between students’ epistemological understanding of models and modelling and their cognitive processing (i.e., deep versus surface processing) on a modelling task. Twenty‐six students, working in dyads, were observed while working on a computer‐based modelling task in the domain of physics. Students’ epistemological understanding was assessed on four dimensions (i.e., nature of models, purposes of models, process of modelling, and evaluation of models). Students’ cognitive processes were assessed based on their verbal protocols, using a coding scheme to classify their types of reasoning. The outcomes confirmed the expected positive correlation between students’ level of epistemological understanding and their deep processing (r = 0.40, p = .04), and the negative correlation between level of epistemological understanding and surface processing (r = ?0.51, p = .008). From these results, we emphasise the necessity of considering epistemological understanding in research as well as in educational practice.     

Exploring Middle School Students’ Understanding of Three Conceptual Models in Genetics

Genetics is the cornerstone of modern biology and a critical aspect of scientific literacy. Research has shown, however, that many high school graduates lack fundamental understandings in genetics necessary to make informed decisions about issues and emerging technologies in this domain, such as genetic screening, genetically modified foods, etc. Genetic literacy entails understanding three interrelated models: a genetic model that describes patterns of genetic inheritance, a meiotic model that describes the process by which genes are segregated into sex cells, and a molecular model that describes the mechanisms that link genotypes to phenotypes within an individual. Currently, much of genetics instruction, especially in terms of the molecular model, occurs at the high school level, and we know little about the ways in which middle school students can reason about these models. Furthermore, we do not know the extent to which carefully designed instruction can help younger students develop coherent and interrelated understandings in genetics. In this paper, we discuss a research study aimed at elucidating middle school students’ abilities to reason about the three genetic models. As part of our research, we designed an eight-week inquiry unit that was implemented in a combined sixth- to eighth-grade science classroom. We describe our instructional design and report results based on an analysis of written assessments, clinical interviews, and artifacts of the unit. Our findings suggest that middle school students are able to successfully reason about all three genetic models.     

Identifying the Item Hierarchy and Charting the Progression across Grade Levels: Surveying Taiwanese Students’ Understanding of Scientific Models and Modeling

The purpose of this study was, first, to understand the item hierarchy regarding students’ understanding of scientific models and modeling (USM). Secondly, this study investigated Taiwanese students’ USM progression from 7th to 12th grade, and after participating in a model-based curriculum. The questionnaire items were developed based on 6 aspects of USM, namely, model type, model content, constructed nature of models, multiple models, change of models, and purpose of models. Moreover, 10 representations of models were included for surveying what a model is. Results show that the purpose of models and model type items covered a wide range of item difficulties. At the one end, items for the purpose of models are most likely to be endorsed by the students, except for the item “models are used to predict.” At the other end, the “model type” items tended to be difficult. The students were least likely to agree that models can be text, mathematical, or dynamic. The items of the constructed nature of models were consistently located above the average, while the change of models items were consistently located around the mean level of difficulty. In terms of the natural progression of USM, the results show significant differences between 7th grade and all grades above 10th, and between 8th grade and 12th grade. The students in the 7th grade intervention group performed better than the students in the 7th and 8th grades who received no special instruction on models.     

Context Dependence of Students’ Views about the Role of Equations in Understanding Biology

Students’ epistemological views about biology—their ideas about what “counts” as learning and understanding biology—play a role in how they approach their courses and respond to reforms. As introductory biology courses incorporate more physics and quantitative reasoning, student attitudes about the role of equations in biology become especially relevant. However, as documented in research in physics education, students’ epistemologies are not always stable and fixed entities; they can be dynamic and context-dependent. In this paper, we examine an interview with an introductory student in which she discusses the use of equations in her reformed biology course. In one part of the interview, she expresses what sounds like an entrenched negative stance toward the role equations can play in understanding biology. However, later in the interview, when discussing a different biology topic, she takes a more positive stance toward the value of equations. These results highlight how a given student can have diverse ways of thinking about the value of bringing physics and math into biology. By highlighting how attitudes can shift in response to different tasks, instructional environments, and contextual cues, we emphasize the need to attend to these factors, rather than treating students’ beliefs as fixed and stable.     

Perceptual Influence of Ugandan Biology Students’ Understanding of HIV/AIDS

In Uganda, curbing the spread of HIV/AIDS has largely depended on public and private media messages about the disease. Media campaigns based on Uganda’s cultural norms of communication are metaphorical, analogical and simile-like. The topic of HIV/AIDS has been introduced into the Senior Three (Grade 11) biology curriculum in Uganda. To what extent do students’ pre-conceptions of the disease, based on these media messages influence students’ development of conceptual understanding of the disease, its transmission and prevention? Of significant importance is the impact the conceptions students have developed from the indirect media messages on classroom instruction on HIV/AIDS. The study is based in a theoretical framework of conceptual change in science learning. An interpretive case study to determine the impact of Ugandan students’ conceptions or perceptions on classroom instruction about HIV/AIDS, involving 160 students aged 15–17, was conducted in four different Ugandan high schools: girls boarding, boys boarding, mixed boarding, and mixed day. Using questionnaires, focus group discussions, recorded biology lessons and informal interviews, students’ preconceptions of HIV/AIDS and how these impact lessons on HIV/AIDS were discerned. These preconceptions fall into four main categories: religious, political, conspiracy and traditional African worldviews. Results of data analysis suggest that students’ prior knowledge is persistent even after biology instructions. This has implications for current teaching approaches, which are mostly teacher-centred in Ugandan schools. A rethinking of the curriculum with the intent of offering science education programs that promote understanding of the science of HIV/AIDS as opposed to what is happening now—insensitivity to misconceptions about the disease—is needed.     

Characteristics and Levels of Sophistication: An Analysis of Chemistry Students’ Ability to Think with Mental Models

This study employed a case-study approach to reveal how an ability to think with mental models contributes to differences in students’ understanding of molecular geometry and polarity. We were interested in characterizing features and levels of sophistication regarding first-year university chemistry learners’ mental modeling behaviors while the learners were solving problems associated with spatial information. To serve this purpose, we conducted case studies on nine students who were sampled from high-scoring, moderate-scoring, and low-scoring students. Our findings point to five characteristics of mental modeling ability that distinguish students in the high-, moderate-, and low-ability groups from one another. Although the levels of mental modeling abilities have been described in categories (high, moderate, and low), they can be thought of as a continuum with the low-ability group reflecting students who have very limited ability to generate and use mental models whereas students in the high-ability group not only construct and use mental models as a thinking tool, but also analyze the problems to be solved, evaluate their mental models, and oversee entire mental modeling processes. Cross-case comparisons for students with different levels of mental modeling ability indicate that experiences of generating and manipulating a mental model based on imposed propositions are crucial for a learner’s efforts to incorporate content knowledge with visual-spatial thinking skills. This paper summarizes potential factors that undermine learners’ comprehension of molecular geometry and polarity and that influence mastery of this mental modeling ability.     

Preservice Biology Teachers’ Conceptions About the Tentative Nature of Theories and Models in Biology

In research on the nature of science, there is a need to investigate the role and status of different scientific knowledge forms. Theories and models are two of the most important knowledge forms within biology and are the focus of this study. During interviews, preservice biology teachers (N = 10) were asked about their understanding of theories and models. They were requested to give reasons why they see theories and models as either tentative or certain constructs. Their conceptions were then compared to philosophers’ positions (e.g., Popper, Giere). A category system was developed from the qualitative content analysis of the interviews. These categories include 16 conceptions for theories (n _tentative = 11; n _certain  = 5) and 18 conceptions for models (n _tentative = 10; n _certain = 8). The analysis of the interviews showed that the preservice teachers gave reasons for the tentativeness or certainty of theories and models either due to their understanding of the terms or due to their understanding of the generation or evaluation of theories and models. Therefore, a variety of different terminology, from different sources, should be used in learning-teaching situations. Additionally, an understanding of which processes lead to the generation, evaluation, and refinement or rejection of theories and models should be discussed with preservice teachers. Within philosophy of science, there has been a shift from theories to models. This should be transferred to educational contexts by firstly highlighting the role of models and also their connections to theories.     

The EvoDevoCI: A Concept Inventory for Gauging Students’ Understanding of Evolutionary Developmental Biology

The American Association for the Advancement of Science 2011 report Vision and Change in Undergraduate Biology Education encourages the teaching of developmental biology as an important part of teaching evolution. Recently, however, we found that biology majors often lack the developmental knowledge needed to understand evolutionary developmental biology, or “evo-devo.” To assist in efforts to improve evo-devo instruction among undergraduate biology majors, we designed a concept inventory (CI) for evolutionary developmental biology, the EvoDevoCI. The CI measures student understanding of six core evo-devo concepts using four scenarios and 11 multiple-choice items, all inspired by authentic scientific examples. Distracters were designed to represent the common conceptual difficulties students have with each evo-devo concept. The tool was validated by experts and administered at four institutions to 1191 students during preliminary (n = 652) and final (n = 539) field trials. We used student responses to evaluate the readability, difficulty, discriminability, validity, and reliability of the EvoDevoCI, which included items ranging in difficulty from 0.22–0.55 and in discriminability from 0.19–0.38. Such measures suggest the EvoDevoCI is an effective tool for assessing student understanding of evo-devo concepts and the prevalence of associated common conceptual difficulties among both novice and advanced undergraduate biology majors.     

Using Interactive Technology to Support Students’ Understanding of the Greenhouse Effect and Global Warming

In this work, we examine middle school students?? understanding of the greenhouse effect and global warming. We designed and refined a technology-enhanced curriculum module called Global Warming: Virtual Earth. In the module activities, students conduct virtual experiments with a visualization of the greenhouse effect. They analyze data and draw conclusions about how individual variables effect changes in the Earth??s temperature. They also carry out inquiry activities to make connections between scientific processes, the socio-scientific issues, and ideas presented in the media. Results show that participating in the unit increases students?? understanding of the science. We discuss how students integrate their ideas about global climate change as a result of using virtual experiments that allow them to explore meaningful complexities of the climate system.     

Students’ Participation in an Interdisciplinary, Socioscientific Issues Based Undergraduate Human Biology Major and Their Understanding of Scientific Inquiry

The purpose of this study was to examine whether Socioscientific Issues (SSI) based learning environments affect university students’ epistemological understanding of scientific inquiry differently from traditional science educational contexts. We identify and compare conceptions of scientific inquiry of students participating in an interdisciplinary, SSI-focused undergraduate human biology major (SSI) and those participating in a traditional biology major (BIO). Forty-five SSI students and 50 BIO students completed an open-ended questionnaire examining their understanding of scientific inquiry. Eight general themes including approximately 60 subthemes emerged from questionnaire responses, and the numbers of students including each subtheme in their responses were statistically compared between groups. A subset of students participated in interviews, which were used to validate and triangulate questionnaire data and probe students’ understanding of scientific inquiry in relation to their majors. We found that both groups provided very similar responses, differing significantly in only five subthemes. Results indicated that both groups held generally adequate understandings of inquiry, but also a number of misconceptions. Small differences between groups supported by both questionnaires and interviews suggest that the SSI context contributed to nuanced understandings, such as a more interdisciplinary and problem-centered conception of scientific inquiry. Implications for teaching and research are discussed.     

Students’ Understanding of Conservation of Matter,Stoichiometry and Balancing Equations in Indonesia

This study examines Indonesian students’ understanding of conservation of matter, balancing of equations and stoichiometry. Eight hundred and sixty‐seven Grade 12 students from 22 schools across four different cities in two developed provinces in Indonesia participated in the study. Nineteen teachers also participated in order to validate the 25‐question survey used with all students. Significant differences in student success in answering specific questions occurred when comparing high‐achievement and low‐achievement schools. However, in general, student understanding of this fundamental principle in chemistry was low. The study found that the average score for all students on the survey was 41%. The findings suggest that students are most successful in solving problems used by teachers and textbooks that are algorithmic‐based (i.e., stoichiometry). As there were no strong positive correlations between student performance on conceptual questions and algorithmic questions, we suggest that further research should focus on teaching practices and curricula that support the development of the students’ conceptual understanding.     

Evaluation of Students’ Understanding of Thermal Concepts in Everyday Contexts

The aims of this study were to determine the underlying conceptual structure of the thermal concept evaluation (TCE) questionnaire, a pencil-and-paper instrument about everyday contexts of heat, temperature, and heat transfer, to investigate students’ conceptual understanding of thermal concepts in everyday contexts across several school years and to analyse the variables—school year, science subjects currently being studied, and science subjects previously studied in thermal energy—that influence students’ thermal conceptual understanding. The TCE, which was administered to 515 Korean students from years 10–12, was developed in Australia, using students’ alternative conceptions derived from the research literature. The conceptual structure comprised four groups—heat transfer and temperature changes, boiling, heat conductivity and equilibrium, and freezing and melting—using 19 of the 26 items in the original questionnaire. Depending on the year group, 25–55% of students experienced difficulties in applying scientific concepts in everyday contexts. Years of schooling, science subjects currently studied and physics topics previously studied correlated with development of students’ conceptual understanding, especially in topics relating to heat transfer, temperature scales, specific heat capacity, homeostasis, and thermodynamics. Although students did improve their conceptual understandings in later years of schooling, they still had difficulties in relating the scientific concepts to their experiences in everyday contexts. The study illustrates the utility of using a pencil-and-paper questionnaire to identify students’ understanding of thermal concepts in everyday situations and provides a baseline for Korean students’ achievement in terms of physics in everyday contexts, one of the objectives of the Korean national curriculum reforms.     

Changes in University Students’ Explanation Models of DC Circuits

One well-known learning obstacle is that students rarely use the concepts in the way that scientists use them. Rather, students mix up closely related concepts and are inclined towards matter-based conceptualisations. Furthermore, some researchers have argued that certain difficulties are rooted in the student’s limited repertoire of causal schemes. These two aspects are conveniently represented in the recent proposal of the systemic view of concept learning. We applied this framework in our analyses of university students’ explanations of DC circuits and their use of concepts such as voltage, current and resistance. Our data consist of transcribed group interviews, which we analysed with content analysis. The results of our analysis are represented with directed graphs. Our results show that students had a rather refined ontological knowledge of the concepts. However, students relied on rather simple explanation models, but few students were able to modify their explanations during the interview. Based on the analysis, we identified three processes of change: model switch, model refinement and model elaboration. This emphasises the importance of relevant relational knowledge at a later stage of learning. This demonstrates how concept individuation and learning of relational structures occurs (and in which order) and sets forth interesting research questions for future research.