Asia-Pacific Forum on Science Learning and Teaching, Volume 15, Issue 2, Article 6 (Dec., 2014) Funda ÖRNEK Do pre-service science teachers have understanding of the nature of science?: Explicit-reflective approach Previous Contents Next

Results

This part elucidates pre-service science teachers’ views of the NOS in pre-instruction and post-instruction focusing on the aforementioned aspects of the NOS. It also reveals their views about the NOS from the post-interviews conducted at the end of the course and during the NOS workshop conducted in the Spring 2009. The transcripts and quotations from the pre-test and post-test, interviews, and video records contain the following shorthand notation: [ ] represents comments about the interview added after the fact, {…} indicates that unimportant words were omitted from the transcript, and inaudible words or sentences were not included. Pseudonyms were used to protect privacy.

Pre-service Science Teachers’ Views of the NOS

Pre–Instruction and Post-Instruction

The results of the data analysis from the surveys indicated that there were pre-to post-test differences in pre-service science teachers’ views of the NOS. However, they still held naïve views about some aspects of the NOS. At the beginning of the course, pre-service science teachers held many misconceptions regarding aspects of the NOS, according to the results of the VNOS-C and the Myths of Science survey. None of them held expert views of all aspects about the NOS in the pre-instruction even though a few had expert views on the certain aspects. Table 1 presents a summary of the results from the VNOS-C and the Myth of Science surveys administered as a pre-and post-test. Table 2 shows the numbers and percentages of pre-service science teachers who held naïve and expert views of the NOS with regard to the aspects of the NOS before the instruction and after the instruction. As seen Table 1 and 2, the majority of pre-service science teachers held naïve views of the seven aspects of the NOS. None of the pre-service science teachers held expert views of all seven aspects of the NOS at the beginning of the study, which was expected (Akerson, Abd-El-Khalic, & Lederman, 2000) because none of the pre-service science teachers had a course related to the philosophy of science or the nature of science. Therefore, none of them were given opportunities to conceive of science as a human endeavor.

Table 1 and Table 2 show that there was a substantial increase in pre-service science teachers who held expert views of the aspects of the NOS at the end of study. There were significant changes in each aspect of the NOS. Nevertheless, the changes were not complete. They still demonstrated naïve views about some aspects of the NOS even after the course. However, one aspect of the NOS that all pre-service science teachers mastered was the tentativeness of science. In Table 1, the quotes presented in column 2 (pre-test) illustrate views that were considered naïve. Quotes illustrating more expert views were presented in column 3 (post-test).

Table 1. Pre-service science teachers’ views of NOS from pre-and post tests

Aspects of NOS	Pre-test	Post-test
Tentativeness	Naïve-science is not tentative “Scientific knowledge cannot change because it is absolute.”	Development “Yes, scientific theory can change if new observation or evidence is found. For example, atom theory has changed many times depend on scientists’ imagination and evidences…” “Scientific theory might change by time because it put by human opinions which may be true or wrong, for example biologists first proposed that the genetic material is composed of proteins. Then, this was changed and moved to be nucleic acids (genetic material is composed of nucleic acids).”
Empirical basis	Mostly Naïve- science is based on experiments. “Development of scientific knowledge requires experiments, because experiments will test and prove the facts and show the true roles that will guide to more understanding and more true facts of science.” “…because the knowledge in science is gained through research and that research doing by experiment and the experiment is important and essential and the main structure of scientific knowledge as a backbone…”	Still Naïve- but development in TCs’ views of this aspects. “It [science] is a human endeavor that to explain how the world works.” “[Science] is the effort to discover, and increase human understanding of how the physical world works. Through controlled methods, scientists use observable physical evidence of natural phenomena to collect data, and analyze this information to explain what and how things work.”
Subjectivity (theory-ladennes)	Mostly Naïve- science is universal. “Science is universal and does not depend on the social and cultural values because science is the same in every where does not affected…”	Still Naïve- but development in TCs’ views of this aspects. “…because they [scientists] have different ways of thinking and analysis of the data.” “Because every scientist look at data from different side and think differently and each group deal and use this data in different way or procedure…”
Creativity/imagination	Mostly Naïve- scientists do not use creativity/imagination at all stages of investigation. “I think scientists use their creativity and imagination during their investigations. The use of imagination and creativity in planning and designing to help them in their work. The imagination and creativity can be used during or after collecting the data but in low levels.” “Yes, I believe that they [scientist] use their imagination. That is satisfied by theories. Theories are type of imagination that are used to explain observations and these theories [imagination] can be changed by time. I think scientists use their imaginations after data collection stage to try explain these data and why they come in this way… Scientific method is a universal that because it could be applied anywhere. It is independent on culture and social values.”	Still Naïve- but development in TCs’ views of this aspects. “Yes, in planning and design, to help provide meaning to experience and understanding the knowledge, and to help to collect the data ad develop the method…”[She believed that scientists use their creativity/imagination only at planning and designing stages.] “Scientists use their creativity in almost all stages. To design experiments in order to collect data, and then formulate these data into meaningful hypothesis.”
Social/cultural embeddedness	Mostly Naïve- science is universal. “Science is universal. It doesn’t reflect social or cultural values. That is because science contacts with the nature and events in it. It doesn’t have any relation with social or culture to affect it…” “I agree that science is infused with social and cultural values because science is related to cultural, and social and philosophical assumption, we are Muslim and the knowledge required in Islam but we must take in mind the legitimacy term for example genetic science is important in science but we cannot use all application like cloning in human or animals because it is interference of God’s creation.”	Still Naïve- but development in TCs’ views of this aspects. “Scientist isn’t universal and a part of my religion [Islam]. Each civilization on earth has taken its own route in the pursuit of knowledge and interaction between those civilizations... Therefore there are no universal science on this planet.” “Science should be universal but some time it affected by the culture for example non-Islamic world can use science to make cloning but it’s not acceptable with Islamic world.”
Observations and inferences	Naïve- “…scientists constructed the model depending on observations [inferences] and from experimental conclusions and by recording effects and properties about atoms. [Pre-test-atomic structure].”	Still Naïve- but development in TCs’ views of this aspects. “atom it’s not some thing that you can see, they reach to this structure through imagination, creativity [inference] and through measuring electricity…” “Scientists simulate structures [inference] (e.g. the atom) according to what they got/found from their experiments (e.g.radiations). Scientists may be not 100% sure about the accuracy of models, but they design them based on data/results/effects to simplify their investigations.”
Theories and laws	All Naïve-hypothesis—theory—law “…hypothesis become theories which become laws.”	Still Naïve- but development in TCs’ views of this aspects. “Theories and law are very different kinds of knowledge one simply does not become the other.” “This is the typical sequence but not always necessary. We might have a law without having a theory.”

Table 2. Pre-service science teachers’ views of NOS in percentages from pre-and post tests

	Pre-instruction		Post-instruction
NOS Aspects	Naïve (N/%)	Expert (N/%)	Naïve (N/%)	Expert (N/%)
Tentativeness	25/100	0/0	0/0	25/100
Empirical basis	22/88	3/12	6/24	19/76
Subjectivity (theory-ladenness)	23/92	2/8	4/16	21/84
Creativity/imagination	24/96	1/4	10/40	15/60
Social/cultural embeddenness	23/92	2/8	2/8	23/92
Observations vs inferences	25/100	0/0	6/24	19/76
Theories and laws	25/100	0/0	5/20	20/80

Note: The aim was not to use quantitative analysis, but showing in numbers can provide another way of looking into the data.

Interviews

Table 3 illustrates the results of the interviews with the six pre-service science teachers after the instruction. Profiles of pre-service science teachers generated from the data analysis of these interviews revealed the influence of the workshop on their conceptions of the NOS (Table 3). Only two of them held more expert views of aspects of the NOS. Five of them still held naïve views regarding some aspects of the NOS. For example, three of them exhibited naïve views on the empirical basis of the NOS. They stated that science is based on experiment and conducting experiments is required to assure the results.

Ahmed held several views consistent with the targeted aspects of the NOS after instruction. However, he still held a few naïve views regarding the targeted aspects of the NOS. He viewed that science needs evidence and experiments to validate the results stating that “science depends on evidence and experiment and science needs evidence and experiments to ensure the results”. He also acknowledged scientific knowledge as constructed, rather than discovered. In addition, he was able to link his understanding of the important role of observation and inference in science as being subjective because subjectivity related to scientists’ backgrounds influence how they interpret data. He held complete understanding of the tentativeness of scientific knowledge. As a result of the explicit-reflective NOS instruction, he improved his views on most of the targeted aspects of the NOS, except for the empirical basis of the NOS. He believed that science was different from other subjects because scientists relied exclusively on empirical evidence. On the other hand, he had a conflicting view with respect to observation and inference because he stated that scientists made inferences from data such as bones, DNA, and footprints. Regarding the socio cultural effect of the NOS, he stated that religion influences science.

Aisha demonstrated very good explanations of the targeted aspects of the NOS after the instruction. She acknowledged that scientists have their own explanations for the data they obtained. She was successful in understanding the distinction between observation and inference using the explanation of the dinosaur question. She also indicated that scientists use their imagination and creativity, giving an example that they have to figure out how to put bones of dinosaurs together, then color and shape of them. Her explanation regarding theory was very informative: She pointed out that scientists’ prior experiences and background affect the interpretation of the data. She also explained that religion influences on science because Muslim scientists, for example, interpret the data by considering rules of Islam, so they cannot be objective.

Fatima also had very convincing explanations of the targeted aspects of the NOS. She demonstrated understanding of the aspects of the NOS.

Mariam held naïve views regarding the empirical basis of the NOS as she stated that science was based exclusively on evidence and experiment even though she later indicated that observation and inferences are parts of science. So her views contradicted this aspect of the NOS (observation/inference). On the other hand, she held good explanations regarding other aspects of the NOS, especially concerning theories and laws. She acknowledged that they do not progress in a hierarchical order. It was substantial change because she had thought that hypothesis leads to theories and then to laws. In addition, she held consistent views with other aspects of the NOS (e.g. science involves creativity and imagination in all stages, scientific knowledge is subjective, and religion affects science).

Zahra held mostly naïve views on most aspects of the NOS with conflicting ideas of some aspects of the NOS. For example, she stated that science is objective not subjective; nevertheless, she also mentioned that science depends on scientists’ perspectives. Another example is that she stated that science is tentative, but also that scientific models are fixed. All statements demonstrated that she did not improve her views and had conflicted ideas about some aspects of the NOS.

Afaf held a few naïve views of the aspects of the NOS and did not demonstrate any conflicted ideas of the aspects of the NOS. She articulated clear descriptions of most of the aspects of the NOS. She stated that scientific knowledge changes indicating an expert view of the tentative nature of science. She also articulated theory-ladenness of the NOS indicating that science was influenced by scientists’ background and perspectives. She was aware of observations and inferences were part of science and explained by using dinosaurs’ example saying that scientists made inferences from their observations such as their bones, DNA, and footprints. On the other hand, she stated that imagination and creativity were not included at all stages of investigations especially indicating reporting results whereas these two are used in planning, experimenting, making observations for inferences, analysis of data, interpretation, and reporting results. She seemed to still believe that reporting results should be more objective. Other than this naïve view, she described other aspects of the NOS well and used examples in the interview questions, such as dinosaurs and weather examples.

Table 3. Pre-service science teachers’ views of NOS from interviews

Teacher	Views from interview (after the course)
Ahmed	Science is a body of knowledge. Science depends on evidence and experiment. Science is different from other subjects. Science needs evidence and experiments to ensure your results. Scientific knowledge changes. Science involves imagination. Religion affects science. Scientific model is not fixed. Science is based on both observation and inference (He explained that they [scientists] collected the bone, from the bones of dinosaurs [observation] they found some remains of dinosaurs of bone that collected and joined them…then they imagine the skin and they make it (inference). There is no absolute truth. Theories and laws do not progress into one and another, in the hierarchical sense
Aise	Science is a description of studying how the world works and how the everything in the world operates. Scientific knowledge changes. Science is tentative. Science involves imagination. Scientists’ prior experiences and ideas dictate what and how scientists conduct their work. Religion and culture influences science. Imagination/creativity is used at all stages of investigations. Science involves observation and inferences (…they [scientists] are very accurate in their observations but they see things from different perspectives [inferences]). Theories and laws do not progress into one and another, in the hierarchical sense
Fatima	Science is studying what happens around us, everything in the nature. Science is tentative (science is always changing). Science involves observations and inferences. Scientific knowledge is not absolute truth. Bias is inherent in the development of scientific knowledge (scientists’ prior knowledge and experiences). Scientific model is not fixed. Creativity and imagination are a part of science. Imagination/creativity is used at all stages of investigations (during, planning, experimenting, making observations, and interpretation of data scientists should use their imagination/creativity). Theories and laws do not progress into one and another, in the hierarchical sense
Mariam	Science is based on evidence/experiment. Science is solving a problem around us. Scientific knowledge can change in the future (she gave atomic theory, how it has been changed so far). Observing and inference are parts of science (shape of dinosaurs). Scientists’ ideas are influenced by their prior knowledge and experiences. Religion can affect science (whether prediction). Scientists use their imagination/creativity at all stages of investigations except including results. Theories and laws do not progress into one and another, in the hierarchical sense, for they are distinctly and functionally different types of knowledge.
Zahra	Science is objective more than subjective. Science is the knowledge that depends on what happened our nature like biology science, chemistry, physics science. Science is reality. Science changes (science is tentative). Observations/inferences are part of science (dinosaurs). Science is not influenced by religion. Science depends on scientists’ perspectives. Models are fixed. Imagination/creativity takes place at all stages of investigations. Theories and laws do not progress into one and another, in the hierarchical sense
Afaf	Science is based on observations. Science is about knowledge. Scientific knowledge change continuously. Science is influenced by scientists’ background and perspectives. Observations and inference take place in science (dinosaurs). Imagination/creativity is a part of science (dinosaurs). Science may not provide absolute truth (weather). Imagination/creativity is not used at all stages of investigations. Theories and laws do not progress into one and another, in the hierarchical sense

Workshop

As indicated before, a workshop was conducted in the spring 2009 semester for 3 hours using several hands-on and minds-on activities, such as cube activities. Comprehensive focus was on the aspects of the NOS that were covered in the workshop. Pre-service science teachers had opportunities to reflect and discuss with their groups and the whole class with regard to aspects of the NOS, except theories and laws because it seemed that pre-service science teachers did not have naïve views regarding that aspect of the NOS. I decided to focus on the tentativeness, empirical basis, subjectivity, creativity/imagination, social/cultural embeddedness, and observations/inferences aspects of the NOS.

After the real life activities, were conducted by pre-service science teachers, class discussions took place and they were asked to write their views with regard to the considered aspects of the NOS on the flip chart as seen Figure 6 (a) and (b). Even if they had naïve views regarding some aspects of the NOS, their classmates corrected them such as writing “not flexible (science is not flexible)” then later they changed it and wrote “changeable (science changes)”. Based on analysis of the video record, it was found that some of them still held naïve views of some aspects of the NOS such as tentativeness. It was a very promising result that they stated that science is not objective indicating science is influenced by scientists’ background, views, and their previous experience. In other words, science is inherently biased towards ideas and theories.

They indicated that science is reliable, but tentative which is an expert view of the NOS aspect of tentativeness. They articulated well other aspects of the NOS such as empirical basis saying that science is based on observations and evidence (can be physical or descriptions), but still they thought that experiments were required too. It seemed that they still thought that experiments were the crucial part of science. Regarding subjectivity, they claimed that science was not objective and biased by scientist’s previous experience, knowledge, background, and views (theory-ladennes). They stated that creativity/imagination, and observations/inferences were parts of science too.

On the other hand, it is interesting to see that some of them still thought that science was composed of only Physics, Chemistry, and Biology as seen Figure 6 (b). Others still held naïve views about the definition of science.

(a)

(b)

Figure 6. Pre-service science teachers’ understanding of NOS

Discussions and Implications

In agreement with research done on pre-service and in-service science teachers’ views of the aspects of the NOS (Lederman, 1992; Abd-El-Khalick & BouJaoude, 1997; Akerson, Abd-El-Khalick, & Lederman, 2000; Haidar, 2001; Seung, Bryan, & Butler, 2009), pre-service science teachers held naïve views of most of the aspects of the NOS at the beginning of the study.

The criteria for the grouping of naïve and expert views were based on previous studies on the NOS.

The results of this study demonstrate that the explicit-reflective instructional approach to teach the NOS carried out within the context of the science method course, Teaching and Learning General Science 1 was effective in enhancing pre-service science teachers’ views of the NOS. Pre-service science teachers seemed to make considerable gains in their understanding of the aspects of the NOS, which is consistent with the studies of Khishfe, 2009; Seung et.al, 2009; Akerson et .al, 2000. It was found that the development of the NOS views when stimulated by the explicit NOS instruction. According to the results of surveys, the interviews, and the workshop, their gains were not consistent across all NOS aspects: They made moderately greater increases in their understanding of the tentativeness of the NOS, the distinction between observation and inference, and the relationship between theories and laws. They demonstrated less substantial gains in the case of subjectivity (theory-ladenness), creativity and imagination aspect of the NOS, and the empirical basis of the NOS.

Consistent with the constructivist view, the discrepant gains in pre-service science teachers’ understanding of the aspects of the NOS could be due to the interaction between their pre-instruction and post-instruction NOS views. On the other hand, their differential gains in the preferred understandings of the aspects of the NOS were not equally accessible. Several quotes of pre-service science teachers’ views of the subjectivity (theory-ladenness), creativity and imagination aspect of the NOS, and empirical basis of the NOS after the instruction illustrate this point.

Finally, it cannot be stressed enough that the NOS instruction is not taught in the context of science content courses. Moreover, the NOS instruction is not offered in the traditional science content courses in the departments of the Colleges of Science. With educational reform in most countries, an explicit-reflective instructional approach to teaching the NOS within the context of science content and methodology courses will hopefully promote pre-service science teachers’ understanding of the NOS and start to sensitize them to the workings of scientific endeavors.

In spite of the favorable changes in pre-service science teachers’ views at the end of the study, some of them still held naïve views about one or more of the aspects of the NOS. The biology majors took Teaching and Learning Biology 1 in the same semester and the NOS was also talked in this class. Therefore, it might have some favorable effects on the pre-service science teachers’ views. Furthermore, it seemed that more than a half of the participants developed inconsistencies in understanding of the desired aspects of the NOS. Consistent with research on misconceptions or alternative conceptions (Abd-El-Khalick & Lederman, 2000; Matson & Aprsons, 2006), participants showed the persistence on misconceptions with regard to some aspects of the NOS. It may be because they developed these naïve views of the NOS over years of Bacanion influenced instruction.

The present study has implications not only for the continuing development of the NOS teaching modules, but also for science teacher educators and instructors in college of sciences who wish to design modules for the NOS or to include it in their science courses. For instance, a physics professor can include a topic on the NOS in his/her curriculum before starting the physics topics so that students can be aware of the aspects of the NOS. Otherwise, most of the students will be puzzled when they are eventually exposed to the NOS.

This study represents an initial step in the exploration of pre-service science teachers’ NOS views in Bahrain. The NOS instruction needs to be integrated within different context/contents to address the inconsistency in pre-service science teachers’ views of the NOS. Finally, three hours for the explicit NOS instruction in a workshop is not enough for pre-service science teachers to abandon their naïve views of the NOS and develop their views of the NOS completely. A separate NOS instruction module should be offered in PGDE programme to develop pre-service science teachers’ understanding of aspects of the NOS not embedded into science methodology courses. To enhance students’ understanding of the aspects of the NOS, the module should include at least three types of activities. First, explicit, non-context-based activities, such as the cube activity and the tricky track activity should be included. Second, explicit, context-based activities such as Newton’s paradigm and Einstein’s paradigm should be included too. In this case the situations that are applicable in Newtonian paradigm will not be legitimate in Einstein’s paradigm, so students will understand that scientific knowledge is not fixed and correct for all phenomena. Finally, it should discuss the history of science, such as atomic theory. Students can then recognize that a scientific theory changes over time as the atomic theory has changed over time from the ancient Greek Model of Democristus (400BC), to the Dalton Model (1803), Thomson Model (1897), Rudherford Model (1911), Bohr Model (1922), and Wave Model (modern). These components of the NOS course module can improve students’ understanding about the tentativeness, empirical basis, development, and the social/cultural influences on scientific knowledge, as well as the function of observations and inferences on constructing scientific knowledge, and the relationship between theories and laws can be enhanced.

A future study might investigate the efficacy of each specific approach (explicit, non-context-based, explicit context-based, and history of science) to the development of pre-service science teachers’ knowledge of the NOS. In addition, it would be valuable to conducti a further investigation on how these science teachers actually employ their knowledge of the NOS as they teach science in schools. Moreover, the results can be analyzed by using a 3 categories scheme-naïve, transition, and informed so that the pre-service science teachers’ transition views can be investigated.

Acknowledgement

An earlier version of this paper was presented at the 3rd Redesigning Pedagogy International Conference (CRPP) in May 2009 in Singapore.