The influence of constructivism on nature of Science as an area of research and as a classroom subject

The influence of constructivism on the research of the nature of Science

During the period when cognitive science learning theory was popular, the early researchers on the nature of science were usually using quantitative techniques, mainly paper-and-pencil, in assessment of students' conceptions of the nature of science. Therefore, it is assumed that this learning theory might have greatly influenced the early research on the nature of science.

To highlight studies on nature of science during the time when cognitive science learning theory was popular, this paper discusses several studies. In 1961 Klopfer and Cooley developed the Test on Understanding Science (TOUS) which was to become the most widely used paper-and-pencil assessment test of students' conceptions of the nature of science. Using TOUS and a comprehensive review of several nationwide surveys, Klopfer and Cooley (1961) concluded that high school students' understandings of the scientific enterprise and of scientists were inadequate. In another comprehensive study, Mackay (1971) pre-and-post tested 1,203 Australian secondary students extending across grades 7-10, using TOUS instrument. He found that students lacked sufficient knowledge of (a) the role of creativity in science; (b) the function of scientific models; (c) the roles of theories and their relation to research; (d) the distinctions among hypotheses, laws, and theories; (e) the relationship between experimentation, models and theories, and absolute truth; (f) the fact that science is not solely concerned with the collection and classification of facts; (g) what constitutes a scientific explanation; and (h) the interrelationships among and the interdependence of the different branches of science.

To illustrate studies investigating the effects of a curriculum on students' conceptions using a cognitive learning theory, this paper discusses another study by Klopfer and Cooley (1963). In this study Klopfer developed the first curriculum designed to improve students' conceptions of NOS. The curriculum was called “History of Science Cases for High Schools” (HOSC). The rationale for the curriculum was that the use of materials derived from the history of science would help to convey important ideas about science and scientists. A sample of 108 geographically representative science classes, including biology, chemistry, and physics, with total number of 2,808 students enrolled in them, was used to assess the effectiveness of the HOSC curriculum measured by the TOUS instrument. After a five month treatment period, students receiving the HOSC curriculum exhibited significantly greater gains on the TOUS than the control groups. This result was consistent across disciplines. It was concluded that the HOSC instructional approach was an effective way to improve students' conceptions of the nature of science. The larger sample size used in this study gave it much credibility and it was followed by widespread curriculum development regarding the nature of science in science textbooks.

As illustrated by the above mentioned studies, researchers who conducted studies on the nature of science during the times when cognitive science learning theory was popular, focused on developing instruments which measure students' conceptions and the effectiveness of specially designed curriculum before and after administrating these tests.

By the late 1980s, researchers in science education were beginning to be influenced by the constructivist learning theory, which developed out of Jean Piaget's work. Whereas researchers using a cognitive science learning theory tended to use quantitative techniques in their studies to measure students' conceptions about the nature of science, researchers using a constructivist learning theory tended to use qualitative techniques and started to observe science classrooms to understand how students construct meaning about the nature of science during the lectures.

To illustrate research on the nature of science conducted from a constructivist learning theory perspective, this paper discusses two studies. In a study carried out by Zeidler and Lederman (1989), the researchers observed 18 high school biology teachers and 409 students in their classrooms. In this study, specific attention was focused on the nature of teacher-student interactions and the specific language used in the classroom. It was hypothesized that conceptions of the nature of science may be implicitly communicated to students by the language teachers use in presenting subject matter. In general, when teachers used “ordinary language” without qualification (e.g., discussing the structure of an atom without stressing that it is a model), students tended to adopt a realistic conception of science. This conception views scientific knowledge as true, real, existing independently of personal experience, and where some scientific objects (e.g., atoms, light, ions) have the same ontological status as ordinary objects (e.g., chair, table). Alternatively, when teachers were careful to use precise language with appropriate qualifications, students tended to adopt instrumentalist conception. The instrumentalist view emphasizes the practical utility of scientific explanations, the role of human imagination and creativity in the development of scientific knowledge, the tentative nature of science, and the utility of arbitrary constructs and models. In short, this view is more consistent with the currently accepted view of science.

In the second study Lederman and O'Malley (1990) has called into question prior approaches to assessing students' conceptions of the nature of science as well as previous recommendations for improving students' understandings of the nature of science. In their study the researchers asked a sample of 69 students spanning grades 9-12 to complete four open-ended questions intended to assess students' conceptions of the tentative and revisionary nature of science.The questionnaire was administered at the beginning of the school year and as a posttest at the end of the academic year. After students' pre-and posttest responses were categorized as exhibiting absolutist or tentative views, a stratified sample was selected for a follow-up videotaped interview. During the interview, students were asked to clarify their questionnaire responses and provide information concerning the sources of their beliefs and factors causing beliefs to change. Although responses on the questionnaires indicated that students possessed absolutist view of science, the interviews indicated that the students actually were quite clear in their beliefs that scientific knowledge is tentative. Additionally, students did not view laboratory activities or any other science activities as specifically related to their present views of science. The researchers concluded that the use of interviews to assess students' understandings of the nature of science are essential. In addition, they pointed out the troubles involved when researchers attempt to categorize students' written responses on paper-and-pencil tests. Given that the overwhelming majority of prior research on students' and teachers' conceptions of the nature of science did not involve interviews, the implications about the accuracy of over three decades of data were called into question by the researchers in this study.

As illustrated by these studies, researchers working from a constructivist learning theory perspective emphasized the importance of using qualitative techniques, such as classroom observations and interviews, for gathering data about the students' and teachers' understandings of NOS. These techniques are consistent with constructivist theory in the sense that they try to see the construction of meanings in their actual setting. Thus, a constructivist learning theory perspective appears to have caused researchers to shift their emphasis from quantitative research methods to qualitative research methods for researching the nature of science understandings in American classrooms.