Experiments in Schools and Science Labs An Explicit Nature of Science -Aspect in a Project for a Science Lab for School Students

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1 Experiments in Schools and Science Labs An Explicit Nature of Science -Aspect in a Project for a Science Lab for School Students Stefan Uhlmann, Burkhard Priemer Ruhr-University Bochum, Faculty of Physics and Astronomy Physics Education Universitätsstraße 150, Bochum, Germany uhlmann@physik.rub.de, priemer@physik.rub.de 1. Introduction In Anglo-American research, pupils and students views about the Nature of Science (NoS) have been a well-known issue over the last decades (review e.g. in Lederman 2007). However, this is not the case in German speaking countries. Since the moderate results of international comparative studies (e.g. TIMSS III) have certified German pupils inadequate views about the NoS, more attention is paid on this research topic (e.g. Höttecke 2001, Priemer 2003). According to Lederman (2007) and others, adequate views about NoS have an impact on content learning success. Despite this, NoS seldom is - especially in Germany - a topic in our curriculum and therefore it is not addressed in classroom instruction. This article shows, how a project explicitly addressing NoS as well as Physics contents in a science lab for school students can change this. This new approach is a first attempt to show that it is possible to change pupils views about NoS with a relatively short but explicit instruction. From our point of view, an explicit and well-dimensioned NoS-focus can lead to more adequate views concerning NoS aspects. 2. Science laboratories for school students in Germany ( Schülerlabore ) Besides science centers, museums, and field trips, a new type of informal learning facilities has been established throughout Germany: extracurricular science laboratories for school students. In these labs, school students usually participate in one-day science projects, which are more formal than visits to museums or science centers, but which are still informal in comparison to school instruction. These forms of student-centered science labs offer a high potential of supporting science education. Founded and run by universities and other research institutions, these science labs aim a. at supporting schools in teaching modern science topics and concepts, b. at increasing students interests in science, and c. at attracting future university students in science and engineering domains (Guderian & Priemer, 2008; Priemer, 2008; Priemer, 2006). 3. Nature of Science (NoS) in science laboratories for school students The umbrella association of German science labs for school students LeLa Lernort Labor has, in spite of the strong differences in the conception of the different science laboratories, developed common aims. One of those aims, for example, is the teaching of an up to date image of sciences and technology and their importance for our society (Euler 2005, translated by the authors). Apart from this, keywords falling into the area of Nature of Science can also be found used by the operators of science labs themselves.

2 Many science labs for school students also follow more or less explicitly the aim of positively influencing pupils views about NoS and therefore also of improving young peoples views about sciences, which are often inadequate (e.g. Lederman 2007). Thereby, authentic learning environments of field trips are often believed to transport adequate epistemological beliefs more or less automatically. However, studies allow the conclusion that adequate beliefs about the NoS cannot be conveyed without being made an explicit topic of discussion (Lederman 2006, Uhlmann & Priemer 2009). We are of the opinion that if you make NoSaspects an explicit topic of discussion, you will have the chance of establishing more adequate epistemological believes. The basic questions, namely if and how Science Labs can reach the above-mentioned aims concerning NoS, were the beginning of the here presented project. The project can be labeled with the following three keywords: explicit authentic and reflexive. In the following chapters, those three keywords will be examined in detail. 4. The design of the NoS-project The project has two focuses. One focus lies on plasma physics, more precisely on the physics of plasma spheres and the spectroscopy of the contained gases. Apart from this very important focus on plasma physics, there also is an equivalent epistemological emphasis in this project. Here, the differences of experiments carried out at schools and scientific experiments as well as the pupils beliefs about scientific experiments and scientists are examined. To be able to change their beliefs, the educational objectives have to be well-dimensioned. This essentially means that only parts of the huge NoS-field as well as of the physics field can be made a topic of discussion. In the following, the schedule of the project is introduced in detail. The project was designed for pupils at the age of years and takes about six hours Introduction to the principles of plasma physics Plasma is not a topic occurring in the physics curriculum in Germany. Therefore there is a short presentation introducing the pupils to the world of plasma at the beginning of the project. With the help of simple models and explanations, among others, the following questions are answered: What is plasma in physics?, Why does plasma emit light?, How can one identify the gas of plasma?, How does the plasma sphere work?. Why does it actually make sense to concern oneself with plasma? The introduction motivates by talking about occurrence and application of plasma in nature and technology. As the pupils are supposed to spectroscope plasma independently in the next phase of the project, also the principals of prism spectroscopy are introduced (refraction, dispersion, direct-vision prism, spectroscope). 4.2 Spectroscopy of the filling gases of a plasma sphere For explicitly contrasting the differences between typical school experiments and scientific experiments, the pupils are encouraged to conduct an experiment which methodology was designed similar to Figure 1 spectroscope experiments at schools. The task is to identify the filling gases of a commercially available plasma sphere. For this purpose, the authors developed a detailed list of instructions, which the participants of the project have to follow (see Uhlmann & Priemer 2011). With the help of a hand-held spectroscope (see figure 1) the pupils are supposed to identify the spectrum lines of the plasma sphere.

3 4.3 Introduction to the Nature of Science focus of the project A lot of pupils are unfamiliar with the topic Nature of Science. For this reason, a short presentation introduces them to the most important principals of the Nature of Science and informs them about the basic questions thought about in this meta-physical area. It is, for example, explained that this field is not primarily concerned with physical facts and knowledge, but rather with how knowledge is gained in science. The advisor introduces the following discussion by stating provocative theses. Among others, the following fields are made a topic of discussion: - whether the same experiment can lead to identical results if it is carried out at two different places (and therefore by different scientists with other scientific backgrounds, such as religion, investors, etc.), - whether the data evaluation of a scientific experiment is always objective, - how long scientific experiments take, - where there could be differences between scientific experiments and experiments at schools, - whether scientists work alone, - how scientific experiments are financed, etc. Figure 2 NoS categories The organigram in figure 2 shows further categories of this introductional discussion. This organigram is very important, as it reflects the most important NoS contents addressed in this project. In this phase, the pupils reflect on their views about the NoS focus for the first time. The aim of this discussion is preparing the pupils for the next phase in which they interview physicists as well as discuss the scientific gaining of knowledge with their class. The views

4 mentioned by the pupils are used in a later phase of the project again, when they are contrasted with the beliefs of scientists. 4.4 Development of interviews In this phase, the pupils are separated into six groups. Each group gets four categories of figure 2 and the task to develop questions concerning their categories, which they would like to ask the plasma physics experts of the faculty later on. This group work aims at the conception of a 20 minutes long interview with a focus on epistemology. 4.5 Expert interviews and guided laboratory tours In this phase of the project, the authentic surroundings of the science lab for school students are used explicitly. The participants leave the science lab in groups and contact plasma physics experts of the faculty. None of the experts is instructed before the interviews. The aim of those tours is showing authentic scientific experiments to the pupils (see figure 3). Authenticity, one of the keywords of this project, is ensured in this phase. 4.6 Collecting the results As each group has different categories and therefore also different questions, the groups get the chance of preparing for a short presentation about their results and impressions (questions, the experts answers, laboratory experiences, etc.) for their classmates after the interviews and the guided laboratory tours. 4.7 Reflection of the impressions After the short presentations, the adviser again initiates a discussion. Here, once more, the reflexive character of the project is highlighted. After having gathered and reflected on the scientists views and beliefs, the results are contrasted with the pupils views and beliefs before and after the authentic impressions. The aim here is finding differences. There is a great emphasis on the comparison of those three positions, as this is, in our opinion, a very important reflection on the learning targets in the epistemological area. The adviser explicitly does not try to find a consensus concerning the mostly different beliefs and he/she also does not try to establish the adequate (or even right ) belief, but he/she does discuss the differences and the fact that one cannot establish an adequate understanding and that this is a special characteristic of NoS. Figure 3 pupils in the guided lab tours 5. Experiences from the project and results of the survey It is worth mentioning that the pupils were generally very enthusiastic about NoS as a topic in a science lab. The active participation in the discussions as well as the engaged and creative contributions concerning the development and performance of the expert interviews show this. The participants were able to very quickly familiarize themselves with the epistemological topic. Concerning some aspects, they already had adequate beliefs. For instance, the pupils did not believe in the myth about the lonely scientist even before the project had started. The participants knew that scientists organize themselves in scientific communities to be more

5 effective in their work. Adequate views also occurred in socio-cultural questions. Here the majority of the pupils for example believed that the development of scientific experiments is independent from the country the scientist lives in, the language he speaks, the religion he believes in, et cetera. Moreover, an above-average amount of pupils stated that even scientists doubt their experimental results. The participants views concerning most aspects were, however, rather inadequate. The duration of scientific experiments, for instance, was evaluated in a too unreflected way. Common durations, like in school experiments, for instance, of 45 minutes were often mentioned. Before the project, the participants obviously did not differentiate between typical experiments at school and scientific experiments. Apart from that the pupils seem to predominantly think that experiments always refer to hypotheses, pure explorative phases are rather unknown. Furthermore and in conformity with other surveys (e.g. Aikenhead, 1987; Driver, Leach, Millar & Scott, 1996; Edmondson & Novak, 1993), evidence of naive realistic beliefs was found. The majority of the pupils for example believed that experiments are able to unveil the truth about nature and that scientific experiments are able to prove a theory. Furthermore, some participants also showed an inconsistent answering behavior concerning some parts of the topic. The pupils are, on the one hand, aware of the fact that even in scientific experiments measurement errors can occur, but they, on the other hand, also think that one can avoid measurement errors if one only measures accurately enough. The scientists as well as the authors of this article realized (when reviewing the videos of the interviews) that the pupils asked profound and well thought through questions (compare examples in table 1). The pupils also showed a great interest in working on the physical focus. The high relevance of this physical topic in every day context as well as the enthusiasm of the scientists made a special impression on the pupils. Table 1: Questions students asked Plasma-Physics experts in the interviews: Can an experiment generate 100 percent results and can established laws be valid for ever? So you would say that established laws were questioned again and then were falsified later on? What does a scientist do? Are results and experiments similar, so to say international? Does the result depend on the cultural background or the origin of the scientist? Does it happen that wrong conclusions are drawn from results which count as true then? How important are political decisions? If you compare those experiments to school experiments, in how far does the equipment differ? The introduced project is part of a survey. In a pre-post-follow-up-design the general research interest is showing that it is possible to convey sub-dimensions of NoS aspects in relatively

6 short instructions in combination with physics contents in a science lab by making them an explicit topic of discussion. More than 200 pupils participated in an exploratory study at the Ruhr-University Bochum, Germany. The results show that it is possible to change pupils views about NoS in relatively short interventions (about 6h project) as long as the NoS-focus is well-dimensioned and made an explicit topic of discussion. Furthermore, the study revealed the conclusion that the additional focus in the field of NoS (together with the content focus) does not mean that the pupils do not learn physics contents. 6. Conclusion and implication The aim of the presented approach was to show that it is possible to change pupils views about the NoS concerning a special focus (beliefs about the nature of experiments ) in a oneday project. The experiences from this project as well as the mentioned empirical evaluation survey showed that pupils views can be positively influenced by making NoS aspects an explicit topic of discussion. In our opinion, a relatively small NoS focus is very important. We also believe that different NoS aspects require different methods. Therefore the interviews with scientists and the guided laboratory tours, which are part of this project, are not a necessary prerequisite of teaching other NoS topics. One could also try, for example, to achieve authenticity by using (historical) original sources such as articles or videos of physicists. This is especially important for schools lacking the possibility of using scientific research facilities. The project is meant as a first step. Next steps are transferring this attempt to school by developing more projects with different NoS-aspects and evaluating the efficiency of authentic and explicit NoS-projects at schools. From our point of view, making different NoSaspects a frequent explicit topic of discussion can lead to more adequate epistemological beliefs in a long run. 7. Literature Aikenhead, G. S. (1987). High-School Graduates Beliefs About Science-Technology-Society. III Characteristics and Limitations of Scientific Knowl- edge. Science Education, 71, Baumert, J., Lehmann, R. & Lehrke, M. et al. (1998). Testaufgaben Naturwissenschaften TIMSS 7./8. Klasse (Population 2). Berlin: Max-Planck-Institut für Bildungsforschung Driver, R., Leach, J., Millar, R. & Scott, P. (1996). Young People s Images of Science. Buckingham: Open University Press. Edmondson, K. M. & Novak, J. D. (1993). The Interplay of Scientific Epistomological Views, Learning Strategies, and Attitudes of College Stu- dents. Journal of Research in Science Teaching 30 (6) Euler, M. (2005). Schülerinnen und Schüler als Forscher: Informelles Lernen im Schülerlabor. Naturwissenschaften im Unterricht Physik, 90, Guderian, P. & Priemer, B. (2008). The impact of multiple visits to an informal learning facility on the development of interest in science. In P. J. Gilmer, C. M. Czerniak, J. Osborne, & W. C. Kyle (Eds.), National Association for Research in Science Teaching, Annual Conference 2007, Baltimore, Impact of Science Education Research on Public Policy, CD-ROM Halloun, I. (2001). Student Views about Science: A Comparative Survey. Beirut, Libanon Höttecke, D. (2001). Die Vorstellung von Schülern und Schülerinnen von der Natur der Naturwissenschaft. Zeitschrift für Didaktik der Naturwissenschaften

7 Lederman, N.G. (2006). Syntax of Nature of Science within Inquiry and Science Instruction. In N.G. Lederman, L.B. Flick. Science Inquiry and Nature of Science. (p ), Dordrecht: Springer Lederman, N.G. (2007). Nature of Science: Past, Present, and Future. In N.G. Lederman, S.K. Abell. Handbook of Research in Science Education (p ), Mahwah (N.J.,USA): Lawrence Erlbaum Associates, Inc., Publishers Priemer, B. (2003). Ein diagnostischer Test zu Schüleransichten über Physik und Lernen von Physik eine deutsche Version des Tests Views About Science Survey. In Zeitschrift für Didaktik der Naturwissenschaften (p ), Priemer, B. (2006). Open Ended Experiments about Wind Energy. In E. v. d. Berg, D. v. d. Berg & T. Ellermeijer (Eds.). Group International de Recherche sur l Énseignement de la Physique (GIREP), Confernece 2006 "Modelling in Physics and Physics Education", Amsterdam, Book of Abstracts (p. 77). Ljubljana: GIREP. Priemer, B. (2008). Extracurricular Science Laboratories: an innovative informal learning facility for school students. In proceeding of Groupe International de Recherche sur l Enseignement de la Physique (GIREP), Conference 2008 Physics Curriculum Design, Development and Validation, Nicosia, Book of Abstracts (p ). Ljubljana: GIREP. Uhlmann, S. & Priemer, B. (2008). Können Schülerlabore Ansichten über Naturwissenschaften ändern? In D. Höttecke (Hrsg.), Gesellschaft für Didaktik der Chemie und Physik, Jahrestagung in Essen 2007, Naturwissenschaftlicher Unterricht im internationalen Vergleich. Münster: Lit Verlag. Uhlmann, S. & Priemer, B. (2009). Nature of Science und Plasmaphysik gemeinsam in einem Schülerlaborprojekt In D. Höttecke (Eds.), Gesellschaft für Didaktik der Chemie und Physik, Jahrestagung in Schwäbisch Gmünd 2008, Münster: Lit Verlag Uhlmann, S., Priemer, B. (2011). Das Experiment in Schule und Wissenschaft; ein Nature of Science -Aspekt explizit in einem Projekt im Schülerlabor, Proceedings DPG Conference 2010, (10/2010).