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.     

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.     

Promoting Linguistically Diverse Students’ Short-Term and Long-Term Understanding of Chemical Phenomena Using Visualizations

Ensuring that all students, including English language learners (ELLs) who speak English as a second language, succeed in science is more challenging with a shift towards learning through language-intensive science practices suggested by the Next Generation Science Standards (NGSS). Interactive visualization technologies have the potential to support science learning for all students, including ELLs, by providing explicit representations of unobservable scientific systems. However, whether and how such technologies can be beneficial for these underserved students has not been sufficiently investigated. In this study, we examine the short-term and long-term effects of interactive visualizations in improving linguistically diverse eighth-grade students’ understanding of properties of matter and chemical reactions during inquiry instruction. The results show that after interacting with the visualizations, both ELLs and non-ELLs showed significant improvement in their understanding of the target concepts at the molecular level on both the immediate test and the delayed test (3 months after the study). In particular, aligned with the goals of the NGSS, all students, including ELLs, were able to demonstrate their understanding of how energy and matter are involved in chemistry through developing molecular models, critiquing models, and constructing scientific explanations. This study shows the potential benefits of using interactive visualizations during inquiry instruction as a resource to help all students, including ELLs who are traditionally underserved in mainstream classrooms, develop a more coherent understanding of abstract concepts of molecular processes during chemical phenomena.     

Analysis of Students’ Diagrams Explaining Scientific Phenomena

Research in Science Education - While there has been much interest in the power of student-generated multiple representations to promote student reasoning and conceptual understanding, most studies...     

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.     

University Students’ Understanding of Electromagnetic Induction

This study examined engineering and physical science students' understanding of the electromagnetic induction (EMI) phenomena. It is assumed that significant knowledge of the EMI theory is a basic prerequisite when students have to think about electromagnetic phenomena. To analyse students' conceptions, we have taken into account the fact that individuals build mental representations to help them understand how a physical system works. Individuals use these representations to explain reality, depending on the context and the contents involved. Therefore, we have designed a questionnaire with an emphasis on explanations and an interview, so as to analyse students' reasoning. We found that most of the students failed to distinguish between macroscopic levels described in terms of fields and microscopic levels described in terms of the actions of fields. It is concluded that although the questionnaire and interviews involved a limited range of phenomena, the identified explanations fall into three main categories that can provide information for curriculum development by identifying the strengths and weaknesses of students' conceptions.     

University Students’ Understanding of Chemical Thermodynamics

This study explored undergraduate students’ understanding of the chemistry topic of thermodynamics using a 4-tier diagnostic instrument, comprising 30 questions, and follow-up interviews. An additional objective of the study was to assess the utility of the 4-tier instrument for use in studies on alternative conceptions (ACs) as there has been no study done on it since its introduction in the literature in the year 2010. A total of 296 students majoring in Chemistry at a university in Singapore participated in this study—88 students in the preliminary study, 102 students in the pilot study and 106 students in the main study. This article reports on the results obtained with students in the main study; their age ranges from 20 to 22 years. Comprising answer and reason tiers plus associated confidence ratings, the 4-tier diagnostic instrument enabled the eliciting of 34 ACs harbored by the undergraduates as well as the strengths of these ACs. Of concern to note is that even for questions which were answered correctly, the mean confidence was not very high. The results of this study reiterate the point that thermodynamics is a topic fraught with conceptual difficulties and ACs. Based on the results from this study, the potential of the 4-tier test for AC studies is further underscored. Some implications of the study are discussed.     

Cross-Grade Comparison of Students’ Understanding of Energy Concepts

The aims of this cross-grade study were (1) to determine the level of understanding of energy concepts of students at different academic grades and the differences in understanding between these grades and (2) to analyse the conceptual development of these students. Two hundred and forty-three students at 3 different levels (high school, undergraduate, and postgraduate) participated in this study. The students’ understandings of energy concepts were determined using a questionnaire, which requested them to define the concept verbally, and to represent it graphically. The most important findings of this study may be summarised as follows. Students from the different groups generally succeeded in defining ‘energy’ in a similar way, namely as the ‘ability to do work’. Nevertheless, some students (including those at university) also provided different alternative conceptions related to the energy concept. In addition, some students also found difficulty in visually analysing the relationships between different variables using graphs. This finding could help explain why attainment levels of all groups falls short in questions that involve the graphical representation of data.     

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 High School Students’ Understanding of Electromagnetism

Although electromagnetism is an important component of upper secondary school physics syllabuses in many countries, there has been relatively little research on students’ understanding of the topic. A written test consisting of 16 diagnostic questions was developed and used to survey the understanding of electromagnetism of upper secondary school students in Turkey (n = 120) and England (n = 152). A separate test consisting of 10 questions on the visualization of spatial rotation was used to investigate the hypothesis that students’ ability to visualize three‐dimensional situations from two‐dimensional representations might influence learning of electromagnetism. Many students’ responses showed misunderstandings and inconsistencies that suggested they did not have a coherent framework of ideas about electromagnetism. Common errors included confusing electric and magnetic field effects, seeing field lines as indicating a “flow”, using cause–effect reasoning in situations where it does not apply, and dealing with effects associated with the rate of change of a variable. Performance on the spatial rotation test was, however, only weakly correlated with performance on the electromagnetism questions. The findings suggest the need to develop teaching strategies that help students to visualize magnetic field patterns and effects, and assist them in integrating ideas into a more coherent framework.     

Secondary Students’ Understanding of Basic Ideas of Special Relativity

A major topic that has marked ‘modern physics’ is the theory of special relativity (TSR). The present work focuses on the possibility of teaching the basic ideas of the TSR to students at the upper secondary level in such a way that they are able to understand and learn the ideas. Its aim is to investigate students' learning processes towards the two axioms of the theory (the principle of relativity and the invariance of the speed of light) and their consequences (the relativity of simultaneity, time dilation and length contraction). Based on an analysis of physics college textbooks, on a review of the relevant bibliography and on a pilot study, a teaching and learning sequence consisting of five sessions was developed. To collect the data, experimental interviews (the so-called teaching experiment) were used. The teaching experiment may be viewed as a Piagetian clinical interview that is deliberately employed as a teaching and learning situation. The sample consisted of 40 10th grade students (aged 15–16). The data were collected by taping and transcribing the ‘interviews’, as well as from two open-ended questionnaires filled out by each student, one before and the other after the sessions. Methods of qualitative content analysis were applied. The results show that upper secondary education students are able to cope with the basic ideas of the TSR, but there are some difficulties caused by the following student conceptions: (a) there is an absolute frame of reference, (b) objects have fixed properties and (c) the way events happen is independent of what the observers perceive.     

Village Elders’ and Secondary School Students’ Explanations of Natural Phenomena in Papua New Guinea

This research investigated the sources of explanations and understanding of natural phenomena in terms of the students’ cultural and school science experiences. The first phase involved interviews with eight village elders that probed their explanations and understanding of natural phenomena. The second phase involved the design, development and administration of two questionnaires on natural phenomena to 179 students in a rural boarding high school in Papua New Guinea (PNG). Most village elders gave explanations of many of the phenomena in terms of spirits, spells, magic, religion, and personal experiences. Most school-aged students choose scientific explanations of natural phenomena in terms of what they had learned in school or from personal experiences. However, many choose explanations of the same phenomena about spirits, spells and magic that came from the village, family or home. The study revealed that students’ ideas about natural phenomena are strongly governed and controlled by their school science knowledge in the school setting. It is likely that their own traditional knowledge cannot be identified in a school setting but that questionnaires in the students’ local language be given to students in their villages (as opposed to school). In addition, so as not to diminish the value of this traditional knowledge, science education programs are needed that are able to consider and harmonise traditional knowledge with school science.     

Development and Application of a Three‐Tier Diagnostic Test to Assess Secondary Students’ Understanding of Waves

This study focused on the development and application of a three‐tier multiple‐choice diagnostic test (or three‐tier test) on the nature and propagation of waves. A question in a three‐tier test comprises the content tier, which measures content knowledge; the reason tier, which measures explanatory knowledge; and the confidence tier, which measures the strength of conceptual understanding of the respondents. This paper presents results based on the responses of 243 Grade 10 students after they were formally instructed on the topic. The vast majority of the respondents showed an inadequate grasp of concepts about waves. Eleven alternative conceptions (ACs), which were expressed with confidence by more than 10% of the students, were identified; four of these ACs were expressed with high confidence.     

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.     

Extending Students’Understanding of Mathe matics via Problem-posing

Inmathematicseducationproblem posinghaslongbeenundertheshadowofproblemsolving .Inthelastdecade ,however,researchersstartedtorealizethepoten tialof problemposingandtherehasbeena growingrecognitionoftheneedtoincorporateproblem posingac tivitiesintomathematicsclassrooms .Problemposinghasbeendefinedbyresearchersfromdifferentperspectivesasagenerationofanewproblemorreformulationofagivenproblem ,asaformulationofasequenceofmathematicalproblemsfromagivensitua tion ,asaresultantactivitywhenaprobleminvit…     

Effects of Conceptual Change Texts and Laboratory Experiments on Fourth Grade Students’ Understanding of Matter and Change Concepts

The purpose of this study was to investigate whether conceptual change texts and laboratory experiments are effective in overcoming misconceptions and whether the concepts were acquired permanently when these methods were utilized. In this study, we addressed some topics from the “Matter and Change” unit in science and technology class of elementary 4th grade. Students from three classes of an elementary school participated in the study (N = 104). Students’ misconceptions were determined by administering the “Matter Concept Test” before, immediately after and 13 weeks after the instructional period. The results of the study showed that both conceptual change texts and experiment method were more successful than traditional instruction in overcoming the misconceptions and acquiring permanent knowledge. However, there was not a significant difference between these two alternative approaches in terms of reducing the misconceptions.     

Composition-Effects of Context-based Learning Opportunities on Students’ Understanding of Energy

Context-based learning has become a widespread approach in science education. While positive motivational effects of such approaches have been well established empirically, clear results regarding cognitive aspects of students’ learning are still missing. In this article, we argue that this circumstance might be mainly rooted in the definition of context itself. Based on this argument, we shift from the issue of if contexts are cognitively beneficial to focus on the question of which composition of contexts is, at least by tendency, more effective than another. Based on theories of conceptual change, we therefore conducted a small-scale intervention study comparing two groups of students learning in different sets of contexts focusing on the same scientific concept—the cross-cutting concept of energy. Results suggest that learning in a more heterogeneous set of contexts eases transfer to new contexts in comparison to learning in a more homogeneous set of contexts. However, a more abstract understanding of the energy concept does not seem to be fostered by either of these approaches. Theoretical as well as practical implications of these finding are discussed.