Impact of Dialogic Argumentation Pedagogy on Grade 8 Students’ Epistemic Knowledge of Science

Abstract

This study explores the effect of dialogic argumentation on grade 8 students’ epistemic knowledge of science in physics. A quasi-experimental design was employed to compare experimental (239) and control (240) groups’ epistemic knowledge of science. A pre-intervention and post-intervention physics reasoning test was administered, and small group classroom discussions were also video recorded. Physics teachers in the intervention group had trained for three days about dialogic argumentation and Talking Physics Students Activities manual was also distributed and used in this yearlong intervention. Mann-Whitney U test results indicated that the post-test scores of grade 8 students in the argumentation lessons significantly increased in their level of epistemic knowledge compared to the non-argumentation groups, z =−4.509, p = .000, and r = .21, but not in the pre-test scores, z =−1.038 and p = .299. However, both pre- and post-test scores of both groups were relatively low. The intervention groups showed significant improvements in the quality of their argumentation on the ASAC scale, z = 2.111, p = .035, and r = .56, but not the control groups, z = 1.068 and p = .285. The study found evidence that argumentation-based lessons improved both the epistemic knowledge and the quality of dialogic argumentations of grade 8 students and that students’ level of epistemic knowledge and the quality of their dialogic argumentations were strongly correlated.

1. Introduction

Research in science education indicates that dialogical argumentation is becoming more popular as a beneficial instructional approach for motivating and promoting students’ reasoning skills and their ability to rebuild basic scientific concepts. Dialogical argumentation is a type of classroom debate in which two or more arguers hold opposing viewpoints on a given topic. The goal is to use evidence to support or disprove claims, to socially build concepts through language mediation, and to improve collective understanding [1]. Such discourse, it may be argued, helps students improve their competencies to “explain phenomena scientifically, evaluate and design scientific inquiry, and interpret data and evidence scientifically” [2]. These competencies, in turn, necessitate the integration of three types of scientific knowledge. The first is content knowledge, which is a set of domain-specific concepts and theories that serve as the foundation for scientific reasoning. The second type of scientific knowledge, referred to as procedural knowledge, is an understanding of the procedures and techniques used to back up what science claims to know. Epistemic knowledge, the third type, is knowledge of epistemic constructs, as well as the validation and justification of the claims of science [2, 3, 4, 5]. Many studies have attested the success of dialogical argumentation in improving conceptual knowledge in Africa and elsewhere [6, 7, 8, 9, 10]. However, there are few studies in science education that focus on the impact of dialogical argumentation on epistemic knowledge of science.

This study looks into how students’ epistemic knowledge of science is transformed through dialogical argumentation. As reform documents have repeatedly stated, epistemic knowledge of science is a critical factor in introducing science-as-a-practice in science education [2]. However, the development of scientific knowledge in science education has traditionally focused on content knowledge rather than epistemic and procedural knowledge. On the other hand, the goals of learning science are shifting away from outcomes, such as conceptual learning, problem solving, and science process skills, and toward introducing and developing the competencies and tools needed for scientific knowledge generation and construction [11]. This shift has highlighted the importance of evidence-based argumentation and the role of epistemic knowledge in science.

Developing epistemic knowledge is especially crucial in the cultural context of Africa, where knowledge is commonly constructed on the basis of authoritative statements, such as those made by teachers, elders, or books. Traditional culture in Ethiopia, where this study was conducted, promotes a stereotyped and authoritative view of knowledge [12]. As a result, science teachers perceive and describe scientific knowledge as everlasting truth, a viewpoint that obstructs teachers’ comprehension of how science works and, as a result, the teaching and learning of school science. The dominating teacher-centered approach to science teaching, the prevalence of science classrooms devoid of scientific inquiry, and rote-memory-based school science tests are all-natural extensions of this culture. Africa needs to make significant efforts to transform the nature of its science education to profoundly alter both instructors’ and students’ innate beliefs about knowledge [7]. To effect a paradigm shift in science pedagogy, teachers’ and students’ epistemic knowledge must be significantly improved. In conclusion, past research shied away from a thorough examination of the progression of the three parts of scientific knowledge, notably epistemic knowledge of science. These studies have failed to explore the impact of dialogical argumentation on the development of epistemic knowledge. In this study, we look at how middle school students’ epistemic knowledge is influenced by dialogical argumentation.

The purpose of this study is, thus, to examine the effect of middle school students’ engagement in dialogical argumentation on their epistemic knowledge of science. Specifically, the research questions guiding this study are:

1. To what extent does engagement in dialogical argumentation affect middle school students’ epistemic knowledge?

2. Is there a relationship between the quality of dialogical argumentation generated by middle school students and their level of epistemic knowledge?

This study was part of a wider research project, namely Transforming Pedagogy of STEM Subjects (TPSS), which promotes the transformation of STEM pedagogy in middle schools of Ethiopia through dialogical argumentation.

2. Epistemic knowledge and dialogical argumentation

In this section, we review the existing body of knowledge that focuses on dialogical argumentation and epistemic knowledge.

2.1 Epistemic knowledge

Epistemic knowledge is the knowledge of how we know what we know [2, 4]. Epistemic knowledge is essential to constructing and justifying the knowledge produced by science. Such knowledge empowers one’s functional understanding of the nature of science [13, 14] and its implementation introduces students to the core scientific practices [5]. Knowing and identifying scientific constructs, such as hypothesis and theory, as well as justifying ideas with evidence and comprehending the justification for various modes of scientific research, are all instances of epistemic knowledge [15, 16].

There are several distinct and changeable parameters in the natural world, which are referred to as variables. Variables are identified and isolated to understand their distinct functions and contributions to the observable world. To understand what a given variable contributes to the observed phenomena, it is necessary to control other factors and examine the change brought about by that specific variable. The generation of knowledge in science necessitates an understanding of why a specific method is used, as well as how the method is both systematic and repeatable. This type of understanding is part of epistemic knowledge [4] and students armed with knowledge can identify entities and events in the physical world, create explanatory models of causal links, and explain how they know what they know.

Many academics see science as a body of knowledge and a way of knowing that takes time to develop [13, 17]. Before science’s methodologies acquired the current systemic ways of knowing, it had to travel a long and difficult road. Indeed, many stories of scientists’ faulty viewpoints and incorrect explanations and reasoning advanced to explain many natural phenomena can be found throughout the history of science [17]. Justifications for knowledge claims rely primarily on data-based evidence and the quality of the reasoning employed to support scientific arguments. Depending on the focus of investigations and the nature of the data, such arguments may be hypothetico-deductive (e.g., Copernicus’ argument for the heliocentric system), inductive (e.g., the conservation of energy), or inference to the best explanations (e.g., Darwin’s theory of evolution or Wegener’s argument for moving continents) [2].

Insights into the role and nature of such arguments are critical for the development of scientific literacy, which needs students to understand the constructs and distinguishing qualities of science [2]. Understanding the underpinnings of scientific observations, facts, hypotheses, models and theories, purposes, goals and values of science, and the styles of reasoning used are integral to grasping science. Thus, epistemic knowledge enables us to understand the role and goal of inquiry in producing knowledge, the goal of the inquiry, and the methodology of the inquiry to justify the claims to know. We would, therefore, argue that understanding science requires understanding how we think in science.

2.2 Characterizing features of epistemic knowledge

As previously stated, epistemic knowledge is essential to the scientific process of knowledge development. Epistemic knowledge provides students with an understanding of the constructs employed in scientific reasoning, as well as the constituent aspects of these constructs and their significance in explaining scientific knowledge. Students can appreciate the intellectual achievement of scientific ideas and their growth using this knowledge. Another benefit of epistemic knowledge is that it allows students to think more deeply about the natural phenomenon they are studying through the use of constructs, such as hypothesis, theory, facts, models, and theories. These constructs are important for developing model-based explanations of how the natural world operates, which is what science is all about. Epistemic knowledge also assists students in understanding what constitutes a scientific question and what observations may yield relevant data. Here, the student’s epistemic knowledge is crucial in selecting the appropriate method of empirical investigation and explaining the resulting design. After that, students must analyze and interpret data to determine how the data informs their hypotheses and theories. Students also must ask questions, such as: Do they support one idea over others, help to refute an idea, or suggest an entirely new explanation? In short, epistemic knowledge is the knowledge that explains how scientific claims are supported by data and reasoning in science. Furthermore, epistemic knowledge includes an understanding of how measurement uncertainty affects our level of confidence in our claims to know. Students must also apply several styles of reasoning in science, including deductive, inductive, abductive, analogical, and model-based reasoning. Understanding their role in science requires epistemic knowledge [2, 3, 4, 5, 16, 18, 19].

3. Dialogical argumentation: what is it?

Dialogical argumentation is a discourse that involves reasoning to solve a problem collaboratively and resolve a conflict between ideas [20]. Dialogical argumentation uses dialogs to justify or refute claims based on evidence, construct ideas socially through the mediation of language, and enhance shared understanding [21]. In the classroom, students can engage in argumentative discourses either at an individual or small group level. During the whole class discussion, individual or group leaders’ views can be presented to the group or the whole class, and group leaders or teachers reflect and mediate the co-construction of knowledge.

Dialogical argumentation provides an opportunity for students to see that a problem or a concept may be comprehended in various ways. Each contender of each competing view forwards its claims and supports these claims with evidence or reason. Not convinced arguers can make counterclaims and justify it with reasons or make rebuttals. Through this approach, dialogical argumentation supports students’ scientific literacy, conceptual learning, and improves their epistemic understanding. This section presents some justifications to support dialogical argumentation in science classrooms.

Several studies thus far have linked argumentation with scientific literacy [22, 23, 24, 25]. Many curricula reforms encourage the incorporation of scientific issues relevant to the well-being of society [26, 27]. Using dialogical argumentation, students can evaluate socio-scientific issues and reach evidence-based conclusions. This, in turn, contextualizes, humanizes, and socializes science for students [17]. Involving students in dialogical argumentation about socio-scientific issues have many benefits. First, students learn to structure their arguments in the context of socio-scientific issues. Second, students know how to justify their stances using normative scientific criteria. Third, students learn to take well throughout evaluative judgments.

Dialogical argumentation situates talking at the center of classroom discourse. Provided that dialogical argumentation is dialogic in nature, it also aligns with the socio-cultural view of learning [28, 29]. Alexander [30] mentioned that effective learning requires the interconnection between language, thinking, and knowing. Therefore, classroom discourses should focus on strategies that promote students’ reasoning. Dialogical argumentation is one of such teaching approaches that connect these three constructs mentioned earlier together [31]. Moreover, dialogical argumentation challenge what students know. When students reflect their knowledge, cognitive conflict, which is key to conceptual learning, might surface.

Studies in the history and philosophy of science revealed that scientists often negotiate meaning in their attempt to understand a scientific event. In addition, scientists critically consider and discuss alternative conceptions and competing views to convince their claims to the scientific community. In this manner, Kim and Roth [28] put argumentation at the heart of the practice of science. Kelly and Licona [32] further argue for school science curricula that value and address the various scientific practices discussed in the history and philosophy of science studies, such as modeling, inquiry, and argumentation that played a paramount role in advancing science. These practices should then be represented in school science curricula, with an emphasis on involving students in scientific activities [33]. Argumentation has thus emerged as a key productive strategy in making sense of physics phenomena and partaking in epistemic practices of science.

4. Promoting epistemic knowledge with dialogical argumentation

This study proposes that students’ engagement in dialogical argumentation enhances students’ epistemic knowledge of science. As discussed elsewhere, during dialogical argumentation, students experience the value to consider alternative positions, justifying their own views with evidence to persuade others, and challenging their arguers’ positions [34]. These experiences create favorable conditions for students to facilitate their epistemic understanding. Engaging in considering alternative views, which are supported by evidence, could induce students to think of the idea that there may be more than a single objective reality. In addition, when students give and receive a critique of their ideas, students could recognize the value of argumentation and evidence in constructing scientific knowledge. Previous research has indicated that students’ engagement in dialogical argumentation improves students’ epistemic practices of science, such as providing justifications and justifying claims with evidence and reason [35, 36].

Particularly the findings of Iordanou and Constantinou [35] indicated that as a result of dialogical argumentation, students use and refer to data to support their arguments. In addition, these authors reported a decrease in personal opinions during the argumentative discourse. A shift from unsupported claims toward using evidence to support their claims and providing interpretations for other evidence was observed. The subtle implication of these findings is that argumentation promotes epistemic practices of students. In another study, Kuhn, Zillmer [36] Kuhn et al. confirms that students show improvements in their epistemic understanding of the normative nature of arguments after engaging in dialogical argumentation. The gain in epistemic understanding includes an understanding of what are acceptable claims to knowledge and what are acceptable ways of discourse in science. However, these studies report the progress of epistemic understanding of argumentation without directly measuring epistemic understanding.

Erduran and Dagher [13] claim that including students in argumentation allows them to see science as a logical practice and to assess the strengths and shortcomings that occurred during the process of knowledge construction in science. In short, such rationales position argumentation as an epistemic activity and emphasize the importance of incorporating argumentation as one of the foci of science teaching. The epistemic process involved in developing and evaluating scientific knowledge claims is revealed via argumentation. This epistemic process, in turn, employs epistemic criteria to select evidence, assess claims and evidence, produce counter-claims, and effectively communicate with others. Hence, it is important to assess the epistemic knowledge of students and to investigate the influence of engaging students in dialogical argumentation on their epistemic practices of science. Thus, this study will, therefore, explore how middle school students’ engagement in dialogical argumentation influences their epistemic knowledge of physics.

5. Methodology

5.1 About participants

A convenience sampling technique was used to identify the primary schools. Twelve primary schools, which use English as a medium of instruction, accessible to transport and cooperative to participate in this yearlong study, were identified and participated. All these schools are government schools. In total, 14 classrooms were randomly selected from these schools and assigned as experimental (N = 7) and control (N = 7) groups. From these schools, a total number of 479 Grade 8 students were involved in this study. Among these 479 middle school students, 273 (57.0%) were female and 206 (43.0%) were male. The treatment group comprised 239 (49.9%) students, whereas the control group contained 240 (50.1%) Grade 8 students.

5.2 Research design: mixed methods

We employed a quasi-experimental mixed-method design that combines quantitative postpositivist methods with qualitative constructivist methods. Study subjects, eighth-grade students, were split into an argumentation lesson group and a non-argumentation lesson group, and quantitative data about students’ level of epistemic knowledge were collected from both groups before and after intervention using Epistemic Knowledge Test items. Students’ argumentations were video recorded to gather qualitative data. According to Creswell and Clark [37], a mixed-methods experimental (or intervention) design is an “approach in which the researcher embeds the collection, analysis, and integration of both quantitative and qualitative data within an experimental quantitative research design” (p. 139). To better analyze and interpret the effect of dialogic argumentation on students’ epistemic knowledge, this study needs not only quantitative data from epistemic knowledge test scores but also qualitative data from observations of students’ argumentation. The use of quantitative and qualitative methods together increases the validity of research reports by correlating results from different methods, elaborating results from one method, informing the other method, providing a comprehensive account of results reported by one method, and even contradicting results reported by one method [38]. These features made mixed-methods relevant and appropriate for this study.

Furthermore, the mixed methods experimental (or intervention) design was chosen since the goal of the study was to learn not only about the impact of argumentation classes on epistemic knowledge but also about how the intervention works. we adopted a concurrent embedded mixed-methods experimental design in which quantitative and qualitative data are collected at the same time. To put it briefly, the study adopted a mixed-method experimental design by integrating quantitative and qualitative approaches to science education research [39].

5.3 Context of the study

This study was part of a wider research project called Transforming Pedagogy of STEM Subjects (TPSS), which promotes the transformation of STEM pedagogy in Ethiopia through argumentation. The aim of TPSS was to reduce an overreliance on teacher-centered, didactic teaching and increase the use of students-oriented, dialogical teaching.

TPSS deduced two strategies to achieve its goal. The first strategy was implementing dialogical teaching and the second strategy was implementing dialogical argumentation directly into elementary schools through in-service training. The participant of this study was part of the group addressed in the second strategy. In 2017/2018, TPSS runs a training program for Grade 7 and 8 physics teachers to incorporate argumentation and a more dialogic approach to their physics teaching. In the three-day training, elementary physics teachers analyzed physics teaching, student learning, and the physics curriculum of Ethiopia. Then, they were introduced to scientific reasoning and argumentation theory. They had been also trained on how to stimulate argumentation in their classroom. TPSS uses scaffolding activities, similar to Figure 1, which make students reflect and discuss scientific ideas. This motivates students to adopt specific ways of talking and expressing scientific ideas, and participate in a structured cultural discourse, that is, scientific argumentation, which promotes their learning. The scaffolding activities address common misconceptions identified via science education research and depend on a variety of styles of scientific reasoning typically used in scientific argumentation.

Figure 1.

Scaffolding activities used for video-recorded students’ discourse: Activity for 1st (measuring temperature) and 2nd videoing (force and motion).

6. Overview of the grade 7 and 8 physics curriculum

Physics is one of the natural science disciplines taught in Ethiopian schools in Grades 7 and 8. It was intended that learning physics would help students understand the physical world, conduct observations and experiments relating to physical events and phenomena, and increase their interest in the natural world. Furthermore, the curriculum highlights the significance of physics in the study of other STEM topics as well as students’ comprehension of scientific practices. The student-centered teaching method aims to help students acquire scientific knowledge, skills, and attitudes and build their confidence to apply knowledge gained to solve text-book or real-life problems. To sum up, the Federal Democratic Republic of Ethiopia Ministry of Education has mentioned the following advantages of studying physics at the K-12 levels. These include:

• Understanding the functioning principles of many of our everyday utensils and gadgets’

• learning about nature and how it works,

• applying physics expertise to other fields and disciplines, and

• addressing practical challenges in the real world [26].

So, to understand nature and natural phenomena, physics should be taught by engaging students in scientific practices rather than telling facts to students. The school science curriculum framework clearly indicated that it is the learner-centered approaches and the constructivist epistemology that the teaching-learning process should follow [26, 40]. The Ministry of Education stresses the importance of quality teaching and learning materials to bring quality to science and mathematics education. Students’ textbooks, students’ workbooks, teacher’s guides, teacher’s handbooks, syllabi, minimum learning competency guides, audio-video materials, and other teaching-learning resources are taken to be important in improving science and mathematics education.

Topics covered in the Grade 7 physics textbooks in Ethiopian schools are structured in eight units: Physics and Measurement, Motion, Force and Newton’s Laws of Motion, Work, Energy and Power, Simple Machines, Temperature & Heat, Sound, and Electricity & Magnetism. Grade 8 physics textbook is organized into six units and covers the topics: Physics and Measurement, Motion in One Dimension, Pressure, Heat Energy, Electricity & Magnetism, and Light.

7. About items that measure epistemic knowledge

The physics reasoning test was developed based on a theoretical rationale presented by Kind and Osborne [4]. The test includes items for different styles of reasoning—hypothetical modeling, experimenting, and mathematical-deductive reasoning. In addition, the physics reasoning test is more focused on items allocated to each of the three sub-constructs of scientific knowledge, namely—content, procedural, and epistemic knowledge. A physics reasoning test that contains 20 questions were administered to each group at the beginning and end of the intervention. The physics reasoning test was prepared to measure students’ scientific knowledge, which includes conceptual, procedural, and epistemic knowledge. Since the focus of this study is on epistemic knowledge, we identified items that assess the epistemic knowledge of students.

Among physics reasoning test items, 10 items had been identified as an item that measures epistemic entity of scientific knowledge based on features identified by [2, 4, 5]. These are Item 3, Item 4, Item 5, Item 6, Item 7, Item 8, Item 9, Item 10b, Item 11, and Item 12 (see the Appendix). To identify items that assess epistemic knowledge, four PhD candidates in Science Education at Addis Ababa University were employed. The PhD candidates took courses, namely Scientific Reasoning and Argumentation in Science Education and Assessment in Physics Education; hence, we considered them appropriate to identify items that measure epistemic knowledge. We asked them to categorize each of the 20 items of the physics reasoning test based on the kind of scientific knowledge (either content, procedural, epistemic knowledge, or the combination of any of these). The raters evaluated each of the test items and identified the knowledge the test item was supposed to measure. We compared the scores generated to measure the inter-rater reliability of the categorization of the physics reasoning test with Cohen’s kappa, which was .833. This indicates that it is good to have an excellent agreement between the identification of each item with the knowledge type it assesses.

We automatically assigned an item to its specific knowledge group when an item is categorized in that group by three or more raters. When raters were split about a particular item, discussions were held to clarify and decide using a panel of experts discussion. Twenty-three items were categorized similarly by three or more raters while the remaining three items were split. Further discussions were conducted and two of the items were assigned in the epistemic knowledge category, while the remaining were categorized as procedural knowledge. To sum up, the physics-reasoning test contains three, 12, and 10 items that measure the content, procedural, and epistemic knowledge, respectively. In this study, we used only these 10 epistemic knowledge items (EKIs hereafter). The maximum possible score of the 10 EKIs was 15 points. We present items of EKIs in the Appendix.

The chosen EKIs examine the epistemic construct of deduction as a form of argument in the construction of scientific knowledge, the knowledge required for evaluating scientific experimentation, and the role of scientific theories and ideas in model-based scientific reasoning. The EKIs items are designed to assess how students know what they know in science. All of the items are applicable to Ethiopia’s physics curriculum for middle school students. To capture the notion of epistemic knowledge, we followed the conception of epistemic knowledge as outlined in Refs. [2, 4, 5]. Thus, items in EKIs assess students’ reasoning about how they know that a certain physics concept and phenomenon is right or wrong, their understanding of how data is represented and used to scientifically justify claims and conclusions using evidence, and their knowledge about making inferences.

8. The intervention

The intervention in the middle school began with a visit to local education officers and school directors, where they were informed of the TPSS aims and research plans. We gained authorization from the local education office to perform the study in the chosen middle schools during this visit. The selected middle school physics teachers were then trained.

Talking Physics is a set of educational materials prepared for training by physics education researchers at Addis Ababa University and Durham University. There are three types of booklets available from Talking Physics. The first type, Talking Physics: In-Service Training, introduces dialogic argumentation as a method of shifting physics education away from the traditional teacher-led didactic teaching, which makes students passive and limits their reasoning, and toward more student-centered dialogical teaching. In TPSS, students involved in dialogical argumentation were encouraged to critically analyze ideas using theoretical and empirical evidence. During the training, physics teachers examined the nature of physics education, student learning, and the physics curriculum, with a focus on upper primary physics. The training also included scientific reasoning, argumentation theory, and techniques to encourage dialogic argumentation in the classroom.

Talking Physics: Student Activities, the second booklet, covers 52 teaching activities, all of which were used in the training. All of these activities were carried out by physics teachers utilizing the pedagogy that we had urged them to employ in their physics classes. The final booklet, Talking Physics: Teacher Guide, advises physics teachers on how to modify their classroom instruction. It guides teachers through the process of incorporating dialogical argumentation into their classroom instruction. It also provides suggestions for time and group structure, as well as techniques for incorporating dialogical argumentation into their instruction. In addition, for each exercise, a correct response is provided.

During the training, we addressed the underlying ideas of all 52 activities, how to incorporate these activities into Grade 7 and 8 physics lessons, and the value of student talk in physics instruction. Four teacher education colleges coordinated and administered the three-day training. Talking Physics: Student Activities booklets were distributed to the intervention group at the end of the training.

Teachers used activities to measure students’ scientific knowledge after introducing a topic or before offering a topic to bring forth students’ scientific understanding. Teachers had also described the task to students, telling them what they needed to complete and how much time they had. In addition, teachers went around to different groups and offered questions to spark debate. Teachers encouraged students to discuss their views rather than simply providing the correct answer. Finally, in whole-class discussions, teachers summarized group conversations. Whole-class discussions were essential to first demonstrate why incorrect responses are incorrect and then to provide the correct responses.

9. Data collected

At two time points in the TPSS intervention year, data were collected using pre-tests and post-tests of physics reasoning test and video records of small group discussion tasks. The physics reasoning test instruments were developed for assessing students’ physics knowledge and skills in scientific reasoning and argumentation, respectively. The quantitative data used included the pre-test and the post-test of the physics reasoning test to assess students’ epistemic knowledge. To measure the quality of students’ dialogical argumentation, we took 28 video recordings of middle school students’ group tasks from 14 primary school classrooms. The group discussion used tasks that required students to use scientific reasoning and argumentation. The group was randomly selected and contained three to six middle school students. Overall, 14 video records were gathered for each of the activities in the treatment group and 14 records were gathered for each of the activities in the control group. Students were also encouraged to use any language that gives them a more comprehensive way of expressing their knowledge. All these video recordings were used in this study.

10. Data analysis

10.1 Inferential statistics used

We checked the assumption for normality, and we found that the students’ pre-test and post-test scores of EKIs for both control and experimental groups were not normally distributed. Hence, we used the Mann–Whitney U test to compare the scores of students’ pre-test and post-test scores of EKIs between control and experimental groups (between-subject comparison). We also computed the gains and normalized gains of both groups (within-subject comparison). Excel and SPSS (V.23) were used to analyze the data and visualize the findings using graphs. In addition, this study also explored the quality of dialogical argumentation during students’ argumentative small group discussions using features of ASAC for both treatment and control groups.

10.2 Assessment of scientific argumentation in the classroom (ASAC) observation protocol

Many argumentation frameworks have been developed to analyze episodes of argumentation. ASAC was developed by Sampson, Enderle [41]. Sampson et al.’s main reason for the development of ASAC was to provide a tool “that can be used to assess the nature and quality of argumentation that occurs between students inside the science classroom” (pp. 236). ASAC situated argumentation as a process and targeted conceptual and cognitive, epistemic, and social aspects of argumentation. The conceptual and cognitive aspects of argumentation attempt to assess how students negotiate, make meaning, and develop scientific understanding. Seven ASAC items evaluate the level of in-depth scientific discussion, the use of alternative claims, the notification of discrepancy and the subsequent adjustment of claims or explanations, the level of challenge and negotiation to offered ideas, and the line of reasoning. ASAC’s epistemic components of argumentation assess how students use evidence, theories, and models, how they evaluate evidence, and how they employ scientific languages in their discussions. The epistemic element was comprised of seven items of ASAC. These items assessed features of argumentation, such as how the content was presented, level of evidence usage, the relevance of evidence, quality of inference from data, how the argumentation is framed, and level of connectedness between inferences and observation. The social aspects of argumentation investigate the interaction. Five items examine the social nature of argumentation. This includes students’ reflection of what they know and how they know, respect for ideas, willingness to contribute, and balanced engagement of group members.

The ASAC observation protocol consists of 19 items on a Likert scale that ranges from 0 (Not at all) to 3 (Often), only Item 6 and Item 8 were reversely rated, that is, from 3 (Not at all) to 0 (Often). Sampson and colleagues present an elaborated discussion about the theoretical underpinnings for ASAC and the methodological approaches they followed to confirm the construct validity, criterion validity, and reliability of the ASAC tool [41]. Comparison between ASAC and Toulmin’s Arguments Pattern (TAP) framework considered ASAC as reliable in assessing the quality of students’ argumentation, hence this study used ASAC to examine the quality of argumentation.

11. Results

This study analyzed the EKIs test scores and the ASAC scores to answer the extent and the ways dialogical argumentation affect middle school students’ epistemic knowledge. The level of epistemic knowledge was determined using the students’ scores in 10 EKIs. The overall physics reasoning was pilot tested and found to be valid and reliable (personal communication). The mean EKIs score then was compared progressively between the treatment and control group using SPSS.

11.1 Students’ epistemic knowledge of science

Grade 8 students’ epistemic knowledge of science was evaluated using 10 EKIs that were identified to measure epistemic knowledge. An independent sample t-test was used to determine if there were statistically significant differences in the students’ epistemic knowledge levels over the course of the year. A high score in these 10 EKIs was regarded as a sign of superior epistemic knowledge. The pre-test and post-test mean scores for the treatment and control groups were used to determine the Grade 8 students’ level of epistemic knowledge.

Figure 1 shows the results of this test. The treatment groups’ level of epistemic understanding of science grew from 3.84 (±1.89) pre-test to 5.10 (±2.48) post-test, as measured by the mean test score (SD). The control groups’ level of epistemic knowledge, on the other hand, was somewhat lower in the post-test (4.06 ± 2.35) than in the pre-test (4.14 ± 2.28). Figure 2 shows that the mean score of students in the intervention group showed a slight increase in the post-test compared to their pre-test score. Not much difference was observed between the post-test score compared to their pre-test score for the control group. Additional statistical analyses were conducted to determine whether the mean EKIs score progressed significantly in the treatment group compared to the control group.

Figure 2.

Comparison of treatment and control group on a pre-test and a post-test of mean scores of the 10 epistemic knowledge items (n = 239 treatment group and n = 240 control group).

Students’ scores were checked for statistical assumptions, such as normality, homogeneity, and outliers. Students’ scores in the EKIs were first checked for outliers. A boxplot assessment using SPSS identified seven outliers in the data for each of the control groups’ pre-test and post-test scores and four outliers in the data for treatment groups’ pre-test scores. Rather than removing the outliers, we substituted the values of these outliers with the next largest value (9.1 for control groups and 8.1 for treatment groups) plus small increments to maintain the ranking in the data. The distribution of students’ scores on 10 EKIs appears to be not significantly different from a normal distribution, as evidenced by the histogram and normal Q-Q plot. However, Shapiro–Wilk’s test (p < 0.05) revealed that the distribution of pre-test and post-test scores of both the experimental and control groups was not normal. Having obtained statistical evidence for non-normality, the nonparametric independent samples t-test was conducted to determine whether there was a significant difference between treatment and control groups in the pre-tests and post-tests of EKIs.

A Mann–Whitney U test was used to see if there was a statistically significant difference in the level of epistemic knowledge between the intervention and control groups based on their pre-test mean scores. The distribution (mean rank) of pre-test scores was not statistically significant between intervention and control groups, as indicated by the Mann–Whitney U test (U = 27,126.5, z = 1.04, p = 0.299, r = 0.05). This revealed that at the start of the intervention, Grade 8 students’ epistemic knowledge of science was not substantially different among groups. However, for the post-test results, the Mann–Whitney U test (U = 35,454, z = 4.5, p 0.001, r = 0.19) revealed a statistically significant difference in EKI mean scores between the intervention and control groups. These small-to-medium effect sizes suggested a significant difference in post-test epistemic knowledge between the intervention and control groups. The implication is that engaging in dialogical argumentation has significantly increased the level of epistemic knowledge among Grade 8 students. The findings show that shifting physics instruction from didactic to dialogic may be beneficial.

Furthermore, Wilcoxon Signed Rank Tests were used to see if there was a statistically significant difference in the pre-test and post-test mean scores of both the intervention and control groups’ epistemic knowledge. The level of epistemic knowledge in the control group was not significantly different on post-test scores than on pre-test scores, T = 10,080, z = −0.208, p = 0.835, r = −0.01. However, a significant difference between pre-test and post-test scores was seen in the intervention group—level of epistemic knowledge was significantly higher on the post-test scores than on the pre-test scores, T = 17,220, z = 6.18, p = 0.000, r = 0.40. The medium to large effect sizes suggested a significant difference in the intervention group’s level of epistemic knowledge between pre-test and post-test scores.

Table 1 presented the percentage of the average scores for EKIs before and after implementation of dialogical argumentation, the gain in epistemic knowledge based on EKIs scores, and the normalized gain. In physics education research, computing the normalized gain in studies that use pre- and post-tests are considered as a standard to evaluate curricula and instructional intervention. Normalized gain is the ratio of each student’s improvement divided by capacity for improvement (Hake, 1998). Computation of normalized gains in this study reveals the improvement of students’ epistemic knowledge of science between their pre-test scores and post-test scores. For the treatment group, where dialogical argumentation was used, the gain in epistemic knowledge, as evaluated by EKIs, was shown to be significant (8.40 percent gain) when compared to the control group (0.53 percent gain). Despite the fact that the students’ EKIs scores were found to be very low (usually below the required minimum of 50%), we noticed a slight improvement in students’ epistemic knowledge (a low gain of G = 0.11) for the treatment group compared to a gain (G = −0.01) for the control group.

Method of Teaching	Pre-test	Post-test	Gains	G	N
Dialogical Argumentation Classroom*	25.60	34.00	8.40	0.11	239
Traditional Instruction Classroom*	27.60	27.07	(0.53)	(0.01)	240

Table 1.

Average normalized gain of students’ epistemic knowledge between argumentative and non-argumentative classrooms.

^*

Both pre-test and post-test scores given here are found by changing the student’s mean scores (given in Table 1) into percentages.

11.2 Quality of students’ dialogical argumentation

To assess the quality of students’ dialogical argumentation, we recorded 28 small group discussions; 14 videos from before and after the intervention that engage them in dialogical argumentation for a year. The video records were collected from seven treatment and two control groups. Sampson, Enderle [41] developed an assessment tool, namely ASAC, which enhances the assessment of dialogical argumentation. The ASAC observation protocol considered conceptual, epistemic, and social aspects of argumentation as the fundamental construct during its development. Sampson, Enderle [41] believed that this tool would allow researchers to assess crucial aspects of argumentation, such as its nature and quality, as well as comprehensively analyze students’ arguments.

The ASAC tool consists of 19 items, with seven examining conceptual aspects of argumentation, seven addressing epistemic aspects of argumentation, and the remaining five focusing on the social side of argumentation. Only Item 6 and Item 8 were reversely rated on a scale of 0 (Not at all) to 3 (Often). In this paper, the ASAC observation protocol was used to evaluate and compare the progress of Grade 8 students across all elements of dialogical argumentation as a consequence of pedagogy intervention for a year. To establish the reliability of the ASAC rating of the episodes of argumentation, the first author and the second-rater, a physics teacher educator and PhD candidate in physics education at Addis Ababa University, assessed four randomly chosen episodes of student argumentative group discussion. The ASAC scorings have acceptable inter-rater reliability, as indicated by Cohen’s kappa (κ = 0.775).

The ASAC observation protocol tool was used to rate 28 recorded student argumentative tasks. Table 2 shows the overall ASAC mean scores for each school, as well as the mean scores for conceptual and cognitive aspects, epistemic aspects, and social aspects of argumentation.

Items	Item Descriptions and Dimensions of ASAC	Ctrl-Pre Mean(SD)	Ctrl-Post Mean(SD)	Intvn-Pre Mean(SD)	Intvn-Post Mean(SD)
Cca1	The conversation focused on the generation or validation of claims or explanations	0.43 (0.53)	0.71 (0.49)	0.71 (0.49)	1.43 (0.98)
Cca2	The participants sought out and discussed alternative claims or explanations	0.29 (0.49)	1(0.82)	1 (0.82)	1.14 (0.69)
Cca3	The participants modified their claim or explanation when they noticed an inconsistency or discovered anomalous information	- (−)	0.71 (0.49)	0.71 (0.49)	0.71 (0.49)
Cca4	The participants were skeptical of ideas and information	0.14(0.38)	0.43 (0.53)	0.43 (0.53)	0.57 (0.53)
Cca5	The participants provided reasons when supporting or challenging an idea	0.57(0.79)	1.14 (0.69)	1.14 (0.69)	1.57 (0.98)
Cca6	The participants based their decisions or ideas on inappropriate reasoning strategies	0.86(1.07)	2 (0.58)	2 (0.58)	1.86 (0.69)
Cca7	The participants attempted to evaluate the merits of each alternative explanation or claim in a systematic manner	0.29(0.49)	0.86 (0.69)	0.86 (0.69)	1.43 (0.98)
	Conceptual and Cognitive Aspects	3.57	4.29	6.86	8.71
Ea1	The participants relied on the “tools of rhetoric” to support or challenge ideas	2.29(0.95)	1.29 (0.49)	1.29 (0.49)	1.29 (0.49)
Ea2	The participants used evidence to support and challenge ideas or to make sense of the phenomenon under investigation	- (−)	0.71 (0.76)	0.71 (0.76)	1.43 (0.53)
Ea3	The participants examined the relevance, coherence, and sufficiency of the evidence	0.14 (0.38)	0.43 (0.53)	0.43 (0.53)	1.14 (0.69)
Ea4	The participants evaluated how the available data was interpreted or the method used to gather the data	0.29 (0.49)	0.43 (0.79)	0.43 (0.79)	0.86 (0.9)
Ea5	The participants used scientific theories, laws, or models to support and challenge ideas or to help make sense of the phenomenon under investigation	- (−)	0.29 (0.49)	0.29 (0.49)	0.86 (0.38)
Ea6	The participants made distinctions and connections between inferences and observations explicit to others.	0.14 (0.38)	0.57 (0.53)	0.57 (0.53)	1.14 (0.9)
Ea7	The participants used the language of science to communicate ideas.	0.14 (0.38)	0.57 (0.79)	0.57 (0.79)	1.57 (0.79)
	Epistemic Aspects	3.00	4.29	4.29	8.29
Sa1	The participants were reflective about what they know and how they know.	1 (−)	1.14 (0.38)	1.14 (0.38)	1.43 (0.53)
Sa2	The participants respected what each other had to say.	1.43 (0.53)	1.43 (0.53)	1.43 (0.53)	1.57 (0.53)
Sa3	The participants discussed an idea when it was introduced into the conversation.	0.43 (0.53)	1.14 (0.69)	1.14 (0.69)	1.86 (0.38)
Sa4	The participants encouraged or invited others to share or critique ideas.	0.43 (0.53)	1.43 (0.53)	1.43 (0.53)	1.57 (0.53)
Sa5	The participants restated or summarized comments and asked each other to clarify or elaborate on their comments.	0.57 (0.79)	1 (0.58)	1 (0.58)	1.14 (0.69)
	Social Aspects	3.86	3.57	6.14	7.57
	ASAC Observation Protocol Total Score	10.43	12.14	17.29	24.57

Table 2.

Mean ASAC scores of both treatment and control groups before and after a yearlong intervention in dialogical argumentation.

Figure 3 (and Table 2) depicted the trends of change in the mean scores of different aspects of argumentation and the overall mean scores of ASAC between pre-test and post-test scores of both treatment and control groups. A critical look at the mean scores in Table 2 and the time effect in Figure 3 indicates that the overall quality of dialogical argumentation had shown progress in the treatment group compared to the control group. A Mann–Whitney test was used to determine if there were any significant differences in the quality of dialogical argumentation and various aspects of argumentation generated by the treatment and control groups as a result of their participation in argumentative and non-argumentative instructions, respectively. Here, all the effects are reported at p < 0.05. For the control group, the Mann–Whitney test revealed that there was no significant difference in the mean scores of Conceptual & Cognitive Aspects (U = 17, r = −0.285, p = 0.285), in the mean scores of Epistemic Aspects (U = 11, r = −0.496, p = 0.064), in the mean scores of Social Aspects (U = 21.5, r = −0.853, p = 0.693), and in the total mean ASAC scores (U = 15, r = −0.332, p = 0.214). For the treatment group, there was no significant difference in the mean scores of Conceptual & Cognitive Aspects (U = 14.5, r = −0.35, p = 0.19) and in the mean scores of Social Aspects (U = 16, r = −0.299, p = 0.263). Nevertheless, a statistically significant difference existed in the mean scores of Epistemic Aspects (U = 5.5, r = −0.662, p = 0.013) and in the total mean ASAC scores (U = 8, r = −0.564, p = 0.035).

Figure 3.

Differences in the level of conceptual and cognitive, epistemic, social aspects of argumentation, and the overall ASAC scores between treatment and control groups across time (pre-test and post-test).

11.3 Correlation between epistemic knowledge and dialogical argumentation

Pearson correlation was used to compare students’ epistemic knowledge, as evaluated by mean scores on epistemic knowledge items, and the quality of their dialogical argumentation, as judged by the ASAC observation protocol. The correlation between the mean scores of the epistemic knowledge test and the mean scores of ASAC was done for 14 school cases. The Pearson’s product–moment correlation analysis indicated a strong and positive correlation between mean scores of epistemic knowledge items and mean ASAC scores, r(14) = 0.558*, p = 0.038 (*The correlation is significant at the 0.05 level (two-tailed)). Dialogical argumentation accounts for 31.14% of the variations in middle school students’ epistemic knowledge of science.

Figure 4 provides a scatter plot between mean scores of epistemic knowledge based on mean scores of EKIs and mean scores of ASAC tool and its components of the aspect of argumentation. Figure 4 also depicted the best fitting linear line and the proportion of variance described by the line (R2 = 0.312). The scatter plot in Figure 4 describes the relationship between the development of epistemic knowledge and engagement in dialogical argumentation. This indicates that those who score high on ASAC also scored high in epistemic knowledge items, and vice versa.

Figure 4.

A scatter plot of mean scores of epistemic knowledge items and mean overall scores of ASAC observation protocol.

12. Discussion

This quasi-experimental study aimed at finding the impact of a yearlong engagement in dialogical argumentation on Grade 8 students’ epistemic knowledge of science. The quantitative results presented above showed an overall improvement in epistemic knowledge. In addition, analysis of video recordings of 28 episodes of argumentation revealed improvements in the experimental groups in the quality of dialogic argumentations. The improvements in epistemic understanding of science and the quality of dialogic argumentation were found to be linearly correlated.

Two research questions guided this study. The main purpose of the first research question was to explore Grade 8 students’ prior epistemic knowledge and then to investigate whether learning physics through dialogical argumentation would change their epistemic understandings. The results indicated that both experimental and control groups show low levels of epistemic knowledge. After the intervention, the experimental groups showed a small but significant improvement in their level of epistemic understanding compared to the control group. These findings suggested that dialogic argumentation did facilitate the growth of students’ epistemic understanding of science. Similar positive effects of argumentation on students’ epistemic cognition have been reported in the literature [8, 42, 43]. That is, this result is consistent with previous findings that indicated that argumentation could provide a powerful context for improving students’ epistemic understanding of science [44, 45]. The main purpose of the second question was to investigate whether continuous engagement in dialogic argumentation would improve the quality of student-generated dialogic argumentations and whether the level of epistemic understanding would correlate with the quality of dialogic argumentation. In this study, no explicit instruction was given on how to improve the quality of student argumentation, though we had trained elementary school teachers about dialogical argumentation.

The quality of students’ dialogic argumentations remained very low and unchanged for the conceptual and cognitive aspects of dialogic argumentation and social aspects of dialogic argumentation. However, though the quality of the epistemic aspect of argumentation was still low, statistically significant scores were observed in favor of the experimental group compared with the control group. This was mainly due to students’ poor performance with regard to Item 3 and Item 4 of the conceptual and cognitive criteria and with regard to Item 10, Item 11, and Item 12 of the epistemic criteria in the ASAC protocol. They had the tendency to use commonsense reasoning to support or challenge claims rather than draw on the available evidence and principles, laws, theories, and formulae (Item 10). The second problem was the naïve use of evidence, that is, no or minimal attempts to examine its relevance, coherence, and sufficiency to the wave phenomenon being discussed (Item 10), and the third was making vague inferences (Item 13). Though the Mann–Whitney U test indicated that there was a statistically significant difference in the epistemic aspects of argumentation between experimental and control groups, the raw scores were still low. These results meant that Grade 8 students’ understanding of the way of knowing science and their skills for arguing with supportive evidence and rationale were at a low level. Other researchers also noted that students are unfamiliar with the “norms of scientific argumentation” and misunderstand what counts as good evidence and reasoning in science (e.g., Walker and Sampson [10], Sampson and Clark [46], Simon, Erduran and Osborne [47]) reported similar problems.

Generally, the quality of dialogic argumentation improved. This was expected because dialogic argumentation is a cognitive process that needs the practice to understand the epistemological foundations of science and to develop the ability to reflect on theories and evaluate them using evidence [3, 48, 49]. Nonetheless, this result suggests that sustained engagement in dialogical argumentation has a positive impact on argument quality. This is consistent with Osborne and Erduran’s [34] observation that under adequate instructional settings, students can considerably enhance their ability to argue.

A few studies have also explored the relations between epistemologies and particular scientific practices, such as argumentation [42, 43, 50]. These studies generally focus on the impact of epistemic knowledge on students’ argumentation abilities. For example, Mason and Scirica [43] found that the quality of students’ arguments, counterarguments, and rebuttals correlated with their level of epistemological sophistication. The current study also found a positive or direct association between students’ epistemic knowledge and the quality of their argumentations.

There are some limitations to the current study. The first is the random selection of the groups who participated in a video-recorded small group discussion task. The selected group may not be representative of the classroom. Consequently, it may not depict the complete picture of the classroom. Being aware of this limitation, we had informed teachers to compose a group representative of the classroom. The teachers’ verdicts were used to the trustworthiness of the selected group’s representation. The other limitation could be the influence of instructional approaches used in other school subjects. In this yearlong study, only physics teachers used dialogical argumentation, whereas biology and chemistry teachers were free to use any instructional approach. Thinking that biology and chemistry are part of science, there may be situations that affect the Grade 8 students’ development of argumentation skills and their epistemic knowledge.

To summarize, this study clearly reveals improvements in the level of student argumentation ability as a result of yearlong participation in dialogical argumentation. Similarly, the study demonstrates not only the existence of a positive correlation between students’ level of epistemic knowledge and the quality of their dialogic arguments but also that the correlation was strong. Though the relationship between student argumentation and their epistemic knowledge remains controversial, the outcomes of this study give additional evidence for the presence of a positive association between epistemic knowledge and the quality of dialogic argumentation.

13. Conclusions

Extensive searches for similar findings in relevant science education and learning science literature revealed that the effect of students’ engagement with dialogic argumentation on epistemic knowledge or vice versa appeared to be understudied so far, both in elementary and secondary school physics and in physics teacher training settings. Furthermore, to the best of the researchers’ knowledge, there is no evidence that the quality of dialogic argumentation is linked to the development of epistemic knowledge. Using dialogic argumentation to improve Grade 8 students’ epistemic knowledge and matching epistemic practices in science classes with the epistemic practices of the scientific community has been a necessary but difficult job [15].

This study included 14 upper primary schools from Ethiopia’s three regional states (Addis Ababa, Amhara, and South Peoples). The research was conducted as part of the TPSS project, which ran from 2016 to 2018. Data were gathered by administering physics reasoning tests, which included epistemic knowledge items (EKIs), video recordings of students’ small group discussions, video recordings of whole-class teaching, and audio recordings of teacher interviews before and after the intervention. Teachers in the intervention groups received a three-day training in dialogical argumentation. During the training, these teachers were exposed to the Talking Physics manual (created by the TPSS project), with follow-up talks on how to implement the manual’s activities.

This study’s results indicated that dialogical argumentation was helpful in increasing Grade 8 students’ epistemic knowledge in physics as well as their competence to reason scientifically during arguments. The significant correlation between students’ level of epistemic knowledge and progress in the quality of their dialogical argumentation would imply that dialogical argumentation indeed helps Grade 8 students improve their epistemic knowledge in physics. We statistically compare the mean scores of EKIs for the two groups and observe that there are no plausible reasons why the means of the two groups might be different, other than the possibility that the argumentative instructions do have a differential impact on students’ epistemic knowledge of science compared to the non-argumentative instruction.

The findings from this study have implications for the teaching of science at middle schools. In most middle schools in Ethiopia, science lessons are often taught through lectures and demonstrations. Much emphasis is given to verifying scientific laws and theories, that is, the content and conceptual aspect of scientific knowledge. This suggests that little attention is given to engaging students in a discursive interaction to construct scientific knowledge. Therefore, physics teachers should provide an opportunity to their students to entertain competing views of a certain physical phenomenon when teaching physics and should encourage students’ dialogical discourse. In this study, Grade 8 students demonstrated small but significant improvement in their epistemic knowledge after they had been exposed to dialogical argumentation compared to other Grade 8 students who were not exposed to dialogical argumentation. The low level of both groups of students’ epistemic knowledge of science in the pre-test indicates that their physics lessons do not adequately address and not well integrated the ways of knowing science. Nevertheless, the small and significant improvement of students’ epistemic knowledge in the experimental group because of dialogical argumentation lessons reveals that argumentation is a viable approach to equip students about the knowledge generation and construction mechanism in science. This implies that middle school physics teachers could scaffold their students’ epistemic understanding of science by shifting their teaching toward a dialogical pedagogy. Engaging students in dialogical argumentative tasks will provide the necessary experiences to develop and master the epistemic entities of scientific reasoning. This is also consistent with global efforts to promote student-centered practices through methodological shifts in science instructions. It should also be noted that the positive results in the current study were obtained even though there is a considerable emphasis on teaching through transmission in Ethiopia. The results of this study corroborated prior findings that the transmission mode of teaching is ineffective in promoting science teaching and learning and should be replaced with student-centered instructional strategies, such as dialogic argumentation. Students can use dialogical argumentation to develop an epistemic understanding of the role of scientific evidence and how science operates. As a result, students will be better prepared to make informed decisions concerning various scientific knowledge claims and their applications.

In a summary, this research revealed that students’ participation in argumentative instructions significantly improved their epistemic knowledge and argumentation quality. Furthermore, the study found that a significant change in the quality of argumentation, as measured by ASAC scores, is associated with a significant change in students’ ASAC epistemic scores. Other areas of ASAC, such as conceptual and cognitive aspects, and social aspects, showed no significant changes.

Item 3

Scientists claim the temperature does not change when ice is melting or when water is boiling.

Which graph below supports the scientists’ claim?

Item 4

Scientists say matter can turn from solid to liquid.

How do we know they are right?

1. Because ice can melt to water

2. Because ice can be crushed to powder

3. Because ice expands when it freezes

4. Because ice can be hard as rock

Item 5

Scientists say sound is caused by vibrations

How do we know they are right?

1. Because vibrations can make things break

2. Because you can feel vibrations in the strings of a guitar or a kirar

3. Because we can hear sound coming from a guitar or a kirar

4. Because loud sound can make the ears hurt

Item 6

Scientists say the Earth has a magnetic field.

How do we know they are right?

1. Because we can find magnetic stones in nature

2. Because we can see magnets attract each other

3. Because we can see that the Sun attracts the Earth

4. Because we can see the needle on a compass always pointing to the North

Item 7

Some students think sound travels faster than light.

How do we know they are wrong?

1. Because you can see a lightning before you can hear the thunder

2. Because light travels all the way from the Sun to the Earth

3. Because you can still hear sounds when it is dark

4. Because sound travels faster in water than in air

Item 8

Some students think the Moon, like the Sun, is producing its own light.

How do we know they are wrong?

1. Because the Moon is seldom seen at daytime

2. Because we feel no heat from the Moon

3. Because shadows caused by moonlight are very weak

4. Because the part of the Moon not lit by sunlight is dark

Item 9

Debre thinks boats float because they are made of light material.

Decide if the observations below support or oppose what Debre thinks (tick one box for each observation)

Observation	Supports Debre	Oppose Debre
When you drop a stone in water it sinks, but a; piece of wood floats	□	□
Some boats are made of steel, but still float	□	□
Some stones are very light, but still sinks	□	□

Item 10

The table shows average temperature at different places in Ethiopia

Location	Average temperature (°C)	Altitude (meters above sea level)
Arba Minch	21.8	1278
Dilla	20.6	1572
Bahir Dar	19.6	1797
Hawassa	19.2	1710
Gondar	19.1	1966
Addis Ababa	15.9	2324
Debre Markos	15.9	2462
Dessie	15.2	2491

1. What is the average temperature in Gondar_________________°C?

2. How does temperature change with altitude?

   1. Higher altitude has higher temperature

   2. Higher altitude has lower temperature

   3. There is no clear pattern between altitude and temperature

Item 11

Some students investigated two ways of heating water. One way was hot plate and the other was Bunsen burner.

They heated the same amount of water and measured temperature every 2 minutes. The measurements are presented in the graph:

1. Which heat source (hot plate or Bunsen burner) heated the water fastest?

   __________________________

2. What was the difference in temperature after 10 minutes?

   __________________________

Item 12

The table compares properties of three materials: Wood, rock and iron

Property	Material 1	Material 2	Material 3
Sinks in water?	Yes	No	Yes
Burns easily?	No	Yes	No
Attracted by a magnet?	Yes	No	No

Decide which materials are wood, rock and iron (write the number)

Wood is material number _____________

Rock is material number _____________

Iron is material number _____________