DOES EXPLICIT INSTRU CTION IN THE NATURE OF SCIENCE (NOS) CHANGE TEACHER S CONCEPTIONS OF THE NOS?

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1 Buffler, A. & Laugksch, R.C. (Eds.) (2004). Proceedings of the 12th Annual Conference of the Southern African Association for Research in Mathematics, Science and Technology Education. Durban: SAARMSTE. DOES EXPLICIT INSTRU CTION IN THE NATURE OF SCIENCE (NOS) CHANGE TEACHER S CONCEPTIONS OF THE NOS? RAJAN KURUP, PAUL WEBB, LES MEIRING & LYN WEBB Department of Science, Mathematics & Technology Education, University of Port Elizabeth, South Africa rajan@iafrica.com ; cenppw@upe.ac.za ; cenlfm@upe.ac.za ; cenmlw@upe.ac.za The South African Revised Na tional Curriculum Statement (2002) states that it has become increasingly important for South African science teachers to develop an adequate understanding of key aspects of the nature of science (NOS). In the light of the above, focus group interviews and a questionnaire was administered to three groups of senior phase science teachers in order to investigate whether there is any difference between the understandings of teachers who have had explicit, implicit or no exposure to notions of the NOS from a BE d in-service programme. The first group had completed six months of the BEd (Science and Mathematics) programme offered by the University of Port Elizabeth (UPE) during which time ideas of NOS were implicitly conveyed via science education modules. The second group had completed nearly two years of this programme and had been explicitly exposed to formal notions of the NOS. The third group was not part of the UPE science education programme and had not received any exposure to the NOS from this source. In a ddition to the questionnaire, focus group interviews were conducted to further clarify teacher s responses. The data generated were analysed in terms of a what, for the purposes of this study, have been categorised as contemporary or traditional understandings of the NOS. INTRODUCTION The epistemological issues concerning scientific knowledge and creation of scientific knowledge have been debated and researched extensively by philosophers of science, science educators, curriculum developers and researchers over the past few decades (Lederman 1992). Given the complex and dynamic nature of science, it is not surprising that Alters (1997) and Lederman et al. (2002) suggest that there is neither consensus among philosophers, historians and sociologists of s cience regarding a specific definition of NOS nor a complete agreement on all the aspects that might characterise NOS. Aikenhead and Ryan (1992) suggest that as NOS can be viewed from various perspectives, this may result in teachers and students holding alternative views of the scientific enterprise. Nevertheless, according to Lederman et al. (2002), there is a current shared wisdom and acceptance among philosophers, historians and sociologists of science regarding certain aspects of NOS, i.e., scientific knowledge is tentative; theoryladen; creation of human imagination and influenced by social and cultural values. In addition to these aspects, they have identified the relationships and functions of scientific theories and laws, the distinction between observation and inference and the myth of Scientific Method. There appears to be agreement among major reform movements and researc hers in science education (e.g. American Association for the Advancement of Science 1990 and 1993; National Research Coun cil 1996, Palmquist and Finley 1997; Hodson 1993; Matthews 1988) about the importance of enhancing teachers understanding of the nature of science. According to Palmquist (1997), what teachers teach, and how they teach it, presents a particular view of science to their students. Teaching basic principles and laws of science create the impression that science is a body of knowledge, and choosing mainly content that may be logically deduced from classroom experiments conveys the message that science is limit ed to hypothetical-deductive experimentation that immediately leads to scientific laws. EXPLICIT AND IMPLICIT EXPOSURE TO NOS The current study was carried out using three different groups of senior phase science teachers (BEd 1, BEd 2 and teachers within the same school district who had not registered for the BEd programme). All of these teachers were from schools in the KingWilliam stown district - a rural region of the Eastern 506

2 Cape Province. The BEd 1 group of teachers (n = 51) had no explicit exposure to NOS ideas at the time that they filled in the questionnaire and participated in focus group interviews. However, they have been exposed to a science module with particular focus on the properties of matter. During the delivery of the module, teachers were exposed implicitly to ideas on the revisionary nature of scientific knowledge, the role of historical context in the development of scientific knowledge and notions of constructivist perspectives in analysing learners alternative conceptions. The BEd 2 group of teachers (n = 41) had completed nearly two years of the programme and had been explicitly exposed to formal notions of NOS through a 10 -credit module on this topic. Key elements of this module are show in Table 1. Table 1. Key elements of NOS c overed in the BEd module that explicitly examined the NOS. Domain Major ideas Scientific method Scientific theory Scientific knowledge (SK) Human aspects of a scientist Traditional/Inductivist view of science Limitations of inductivism Falsificationism Scientific inquiry is theory -laden Tentative nature of theory Theories are invented Theories are tools to describe, explain and predict natural phenomena Ad hoc. modifications to theories Theories are developed within the constraints of a paradigm Observations are theory-laden SK is tentative and developmental SK is validated by peer review Development of SK is not continuous SK is developed in a particular socio -political and cultural context Scientists are influenced by social, cul tural and political factors as well as prior knowledge Scientists resist paradigm shift Scientists try to integrate new knowledge into old knowledge Scientists use imagination and creativity in developing knowledge The third group of senior phase science teachers (n = 44) who participated in this study were not part of the BEd programme (non-bed group). All of the teachers in the three groups have an M + 3 qualification and have been teaching science for more than six years. METHOD A twelve-item Likert-type questionnaire (Appendix 1) was developed by considering the key aspects of the NOS as espoused by Lederman et al. (2002). Items in the questionnaire were modified and revised after discussion with five lecturers who have been involved in science educa tion for a number of years in an attempt to improve their validity. The questionnaire was administered to all participants in groups in a formal classroom setting. The answers to the questionnaire items were classified into three categories based on (i) L ederman et al. (2002) current shared wisdom (and so designated as a contemporary view), (ii) views acceptable to positivist/empiricist schools of thought (and designated as traditional for the purpose of this study), and (iii) no opinion for those who felt that they could not articulate any specific opinion on a particular 507

3 statement. Based on this classification a contemporary view is reflected by strongly agree or agree for statements 4, 7, 11 and 12 and strongly disagree or disagree options for th e rest of the statements. The classification of the participants responses into the contemporary category is congruent with the aspects of NOS highlighted in both the Benchmarks (American Association for the Advancement of Science 1993) and Standards (National Research Council 1996). Given the problems associated with the use of forced choice, paper and pencil NOS instruments (Aikenhead et al. 1989), teachers were selected for focus group interviews (with a maximum of five teachers in a group). The purpose of the interviews was: (i) to clarify whether each statement was clear to the participants, (ii) to elucidate on the meaning the participants attached to each statement and (iii) to elaborate on the choices made with examples where possible. These semi -structured interviews assisted in stimulating discussions on pertinent issues and offered insights to participants ideas about various aspects of the NOS. RESULTS Responses to the Likert-type questionnaire are shown in Table 2. The statements are grouped into seven categories, viz. the nature of scientific theories, the nature of scientific knowledge, the role of observation and inference, the role of imagination and creativity, and the social and cultural embeddedness of scientific knowledge. At the stage of writing, the focus group interviews were still in progress with each of the three groups having only one interview each. Despite the small sample interviewed, the data generated by the focus group interviews yielded valuable insights into the particip ants thought processes and enabled us to make greater sense of the quantitative data generated by the Likert -type questionnaire. Table 2. Responses per category in percentages for the 12 statements. Group n Non-BEd 44 Contemporary Positivist No opinion BEd 1 51 Contemporary Positivist No opinion BEd 2 41 Contemporary Positivist No opinion Nature of scientific theories (Statements 1 & 7) Sixty-three percent of the BEd 2 teachers disagreed with the statement that scientific theories reveal the absolute truth (i.e. there is no uncertainty about the truth) while the majority, i.e. 57% and 66% respectively, of BEd 1 and non-bed teachers either agreed with this statement or did not offer an opinion (Table 2). During the focus group interview two of the BEd 2 teachers changed their position from agreeing with this statement to rejecting it. The reason they gave for changing their minds was that th ey thought, on reflection, that scientific theories are revisionary in nature and therefore cannot be held to be true indefinitely. On the other hand, both BEd 1 and non-bed focus groups came to the shared opinion that repeated experimental verification determined the status of a theory. A teacher in the BEd 1 focus group made this particularly explicit by noting that If it is proven over and over and if nothing is disagreeing, then it reveals absolute truth. Proved beyond doubt, cannot change. Paradoxically, the majority of teachers in all of the three groups supported the statement that scientific theories may change with time, with a moderately higher percentage of support by BEd 2 teachers (90%), over the BEd 1 (63%) and non-bed (77%) groups. The reason for this requires further investigation. 508

4 Nature of scientific knowledge and its generation (Statements 2, 6, 9 & 10) There was exceptionally strong support (95%+) by all three groups for the questionnaire statement 2, i.e. that the development of scientific knowledge is an orderly, rational and step-by-step process (i.e. scientists first collect data, and then generate theories by looking for patterns in the data). The focus group interviews revealed that these teachers have a very strong belief that scientists generate knowledge in a step-by-step, sequential order. However, all three groups were much more reserved in their support (less than 50%) for statement 9, i.e. that the Scientific Method is the only way to study nature and natural phenomena. A majority of the teachers (75%+) felt that scientists discover theories and laws (statement 6) and the focus group interviews confirmed that they believed that this knowledge was something which is out there, i.e. an objective reality independent of scientists. The notion that indigenous knowledge (i.e. knowledge held by different cultures) cannot be regarded as scientific knowledge was rejected by 70% and 71% of the non-bed and BEd 2 groups respectively, but an equal number of BEd 1 teachers accepted or rejected the statement, with 14% unable to offer an opinion. The role of observation and inference (Statements 8 & 12) A majority (73%) of the BEd 2 teachers agreed with the view that inference is theory -laden, i.e. they rejected the notion that two independent scientists make the same conclusion from observing a natural phenomenon (e.g. draw the same conclusion after observing a forest fire). During the interviews they articulated their reasons in terms of the fact that an observer is influenced by prior know ledge, social and cultural preferences. Approximately half of the teachers in both of the BEd 1 and non -BEd groups accepted this statement. Statement 12, i.e., that observations made by a scientist can be objective, but the conclusion drawn from the observ ation is subjective was accepted by the majority of both non-bed, BEd 1 and BEd 2 teachers (59%, 67% and 66% respectively). However, this statement had the highest percentage of no opinion responses of all of the statements, suggesting that the teachers possibly found the concept difficult to understand. Role of imagination and creativity (Statement 3) Seventy-six percent of the BEd 1 and 75% of the non-bed teachers appear to hold a mechanistic view about the role of scientists in developing knowledge in that they support the view that scientists perform experiments/investigations when trying to solve problems and they use their imagination and creativity only during the planning and design of these experiments/investigations (statement 3). However, nearly half of the BEd 2 rejected this statement. During the BEd 2 interview the group came to consensus that scientists make use of imagination and creativity not only at the initial stages, but through all stages in the development of knowledge. One BEd 2 teacher expressed his understanding as follows: Scientists make use of imagination and creativity through out the processes. They need to use imagination and creativity until you come to the scientific conclusion. Social and cultural embeddedness of scient ific knowledge (Statement 4) Seventy-eight percent of the teachers in the BEd 2 group agreed with this statement that the theories developed by scientists are influenced by the social, political and cultural contexts (situations) prevailing at that time, compared to only 59 % of the BEd 1 and 41 % of the non-bed teachers. The notion that a scientist is detached from the norms and values of a social fabric is reflected in the following comment made by a non-bed teacher during an interview, viz. I disagree because science has very little to do with social, political and cultural situations. Therefore I strongly disagree. Scientific theories and laws (Statement 5) More than 80% of all teachers in this study appear to adhere to the notion that over time, and after successful experimental verification, scientific theories mature into laws. The prevalence of the perception among teachers that scientific laws are superior to theories was endorsed during all of the interview sessions. However, no teacher was able to articulate a coherent answer to the following question posed by the interviewer: Do you think that, at some stage, all scientific theories will become laws? 509

5 Science-Technology-Society (Statement 11) The quantitative data suggest that a majority of teachers strongly believe that science should not be thought of as being separate from technology. During interviews, some teachers expressed the view that technology is applied science and a few viewed the relationship between science and technology as be ing interactive. DISCUSSION An analysis of the responses by BEd 1 teachers both to the questionnaire items and interview questions suggest that they hold mostly traditional views in a number of aspects of the NOS. During focus group interviews it was noted that very few participants elaborated their views using relevant examples and the few examples that were cited suggested a weak understanding of the epistemological basis of science. Despite the fact that these teachers had been implicitly introduced to notions of the nature of science during science focused modules, the data suggests that they have understandings that are only slightly more contemporary than those of teachers who, in the context of this study, had not recently been introduced to contemporary notions of NOS by implicit or explicit teaching (the non-bed group). Similar studies by Khishfe and Abd-El-Khalick (2002), Gess-Newsome (2002) and Moss et al. (2001) have indicated that implicit instruction in NOS does not meaningfully assist in tea chers or students acquiring desired understandings of the nature of science, and these authors suggest that explicit instruction in terms of modern understandings of the NOS might possibly enhance the achievement of desired outcomes in this area. The quantitative and qualitative data generated in this study suggest that the second year BEd teachers have developed a more contemporary view on certain aspects of NOS and that this may possibly be caused by the explicit instruction they received in NOS during the programme. Deeper probing of what teachers mean by their responses to questionnaires and during interviews is required to get a more meaningful understanding of teachers epistemology in terms of the NOS. Khishfe and Abd -El-Khalick (2002) suggest that the context in which NOS views are presented plays a significant role in enhancing NOS understandings. Similarly, it became evident during the focus group interviews that took place in this study that the most profitable way in which to generate meaningful di scussion around aspects of NOS is to present them in relevant and familiar contexts. It was particularly noticeable that, when aspects such as the revisionary nature of scientific theories were framed in the context of HIV -AIDS, a lively discussion ensued among the participants and that teachers were able to articulate their points of view more clearly and forcibly. ACKNOWLEDGEMENTS Appreciative acknowledgement is made to the South African -Netherlands Research Programme on Alternatives in Development (SANPAD) for financial support for this research. 510

6 REFERENCES Aikenhead, G. & Ryan, G. (1992). The development of a new instrument: Views on Science-Technology-Society (VOSTS). Science Education, 76, Aikenhead, G., Ryan, A. & Desautels, J. (1989). Monitoring Student Views on Science-Technology-Society issues: The development of multiple choice items. Paper presented at the Annual Meeting of the National Association for Research in Science Teaching, San Francisco, California, USA. Alters, B.J. (1997). Whose Nature of Science? Journal of Research in Science Teaching, 34(1), American Association for the Advancement of Science. (1990). Science for all Americans. New York: Oxford University Press. American Association for the Advancement of Science. (1993). Benchmarks for science literacy. New York: Oxford University Press. Gess-Newsome, J. (2002). The use and impact of explicit instruction about the Nature of Science and science inquiry in an elementary science methods course. Kluwer Academic Publishers, 11, Hodson, D. (1993). Philosophic stance of Secondary School science teachers, curriculum experiences, and children s understanding of science: Some preliminary findings. Interchange, 24(1&2), Khishfe, R. & Abd-El- Khalick, F. (2002). Influence of explicit and reflective versus implicit inquiry-oriented instruction on sixth graders views of Nature of Science. Journal of Research in Science Teaching, 39(7), Lederman, N.G. (1992). Students and teachers conceptions of the Nature of Science: A review of the research. Journal of Research in Science Teaching, 29(4), Lederman, N.G., Abd-El-Khalick, F., Bell, R.L. & Schwartz, R.S. (2002). Views of Nature of Science questionnaire: Toward valid and meaningful assessment of learners conceptions of Nature of Science. Journal of Research in Science Teaching, 39(6), Matthews, M.R. (1988). A role for history and philosophy in science teaching. Educational Philosophy and Theory, 20, Moss, D.M., Abrams, E.D. & Robb, J. (2001). Examining student conceptions of the nature of science. International Journal of Science Education, 23(8), National Research Council. (1996). National science education standards. Washington, DC: National Academic Press. Palmquist, B.C. & Finley, F.N. (1997). Pre-service teachers views of the Nature of Science during a post-baccalaureate science teaching program. Journal of Research in Science Teaching, 34(6), Revised National Curriculum Statement Grades R-9 (Schools). (2002). Pretoria: Department of Education. 511

7 APPENDIX 1: VIEWS OF SCIENCE QUESTIONNAIRE There are no right or wrong answers to the following statements. Please read each statement carefully and then circle the option (Strongly Disagree, Disagree, No Opinion, Agree or Strongly Agree) that best describes your view on that statement. # Statement Circle your view 1 Scientific theories reveal the absolute truth (i.e. there is no uncertainty about the truth). 2 The development of scientific knowledge is an orderly, rational and step - by-step process (i.e. scientists first collect data, and then generate theories by looking for patterns in the data). 3 Scientists perform experiments/investigations when trying to solve problems. They use their imagination and creativity only during the planning and design of these experiments/investigations. 4 The theories developed by scientists are influenced by the social, political and cultural contexts (situations) prevailing at that time. 5 After repeated and successful experimental veri fication, a scientific theory becomes a law. 6 Scientists discover theories and laws. 7 Scientific theories may change with time. 8 Two independent scientists make the same conclusion from observing a natural phenomenon (e.g. draw the same conclusion after observing a forest fire). 9 The Scientific method is the only way to study nature and natural phenomena. 512

8 10 Indigenous knowledge (i.e. knowledge held by different cultures) cannot be regarded as scientific knowledge. 11 Science should be thought of as separate from technology. 12 Observations made by a scientist can be objective, but the conclusion drawn from the observation is subjective. 513