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

The nature of Science as a content area

The longevity of the nature of science objective in science education is attested to by the National Society for the Study of Education (1960) and Hurd (1960) who claim the existence of the objective of teaching the nature of science in the American schools as early as 1920. Actually, one can trace the advocacy for students' understandings of nature of science to the reports of the Central Association of Science and Mathematics Teachers (1907) in which a strong argument was presented for increased emphasis on the scientific method and the processes of science. Concerns for the development of adequate understandings on the nature of science “have worn many hats” through the years (Lederman, 1992). In the early 1900s the nature of science objective was expressed in terms of increased emphasis on the scientific method “so as to better train students' mental faculties” (Hurd, 1960); in the 1960s the objective was linked to the advocated emphasis on scientific process and inquiry (Welch, 1979); and most recently it has been included as a critical component of scientific literacy (American Association for the Advancement of Science, 1989; National Science Teachers Association, 1982). Clearly, science educators and scientists have been extremely persistent in their advocacy for improved student understanding of the nature of science. Indeed, Kimball (1968) has referred to this objective as one of the most commonly stated objectives for science education and Saunders (1955) went so far as to describe it as the most important purpose of science teaching.

Research related to the nature of science can be conveniently divided into four related, but distinct, lines of research: (a) assessment of student conceptions of the nature of science; (b) development, use, and assessment of curricula designed to “improve” student conceptions of the nature of science; (c) assessment of, and attempts to improve, teachers' conceptions of the nature of science; and (d) identification of the relationship among teachers' conceptions, classroom practice, and students' conceptions (Lederman, 1992).

Although the belief in the importance of students' understandings of the nature of science has persisted through the twentieth century as mentioned above, assessments of students' conceptions did not start until 1954 (Wilson, 1954). Initial assessments of students' conceptions indicated that students did not possess adequate understandings of NOS and led to the conclusion that science teachers must not be attempting to teach nature of science. A second line of research focusing around curriculum development and assessment was initiated by Cooley and Klopfer (1963). The results of this movement were ambiguous. That is, the same curriculum was effective for one teacher with a particular group of students, but not for another teacher with different group of students. The appropriate conclusion was that the individual science teacher must make a difference. Predictably, a subsequent line of research focused on the assessment of teachers' conceptions. Disturbingly, there was no attempt to focus on the behaviors and other classroom variables related to individual teachers. The assessment of teachers' conceptions of the nature of science indicated that they did not possess the desired level of understanding (Lederman, 1992). Because teachers cannot be expected to purposefully teach what they do not understand, many researchers focused their attention on the development and assessment of techniques designed to improve teachers' understandings of NOS (Lederman, 1992). Unfortunately, the results of such attempts were ambiguous and the specific variables contributing to improved conceptions of NOS remained unknown.

The above mentioned lines of research were informed by two basic implicit assumptions: a teacher's understanding of the nature of science is related to his/her students' conceptions and a teacher's instructional behaviors and decisions are significantly influenced by his/her conceptions of nature of science (Lederman, 1992). Recognition of these assumptions and the results of general research on teaching contributed to a refocusing of researchers' attentions on the testing of these assumptions and attempts to derive those classroom variables related to changes in students' conceptions (Brickhouse, 1990). Interestingly, Trent (1965) had made such recommendations 30 years earlier. As a consequence of this more recent research, it appears that the most important variables that influence students' beliefs about the nature of science are those specific instructional behaviors, activities, and decisions implemented within the context of a lesson. It appears that continued stress on higher-level thinking skills, problem solving, inquiry-oriented instruction, and frequent higher-level questioning within a supportive risk free environment are at least related to desired changes in students' conceptions (Lederman, 1992). There appears to be a clear recognition that each line of research is a piece of a much larger puzzle (Lederman, 1992). There appears to be an overt recognition that teachers can not teach what they do not understand, and that simply possessing the desired knowledge dose not ensure its effective communication to students (Mac Donald & Rogan, 1990). Additionally, science educators' interest in students' conceptions of the nature of science has been placed within the context of constructivist epistemology (Wheatley, 1991) and, within this view, is unavoidably related back to specific classroom activities and instructional approaches. In short, the current state in the area of research on the nature of science is a coherent effort, with researchers building upon and informing each other's work, as it is the case in constructivist learning perspective.

The recent growth of qualitative techniques in research on the nature of science, which are in accordance with constructivist learning theory perspective, has allowed researchers to avoid the problems created by limiting responses to an a priori set of categories or viewpoints (Lederman, 1992). As a consequence, resent research has allowed science educators to identify the wide variety and complexity of perceptions held by both teachers and students, as well as some of the classroom variables related to changes in students' conceptions. Although the results of recent qualitative investigations have not outwardly contradicted the results of prior quantitative approaches, which were using cognitive science learning theory perspective, they have provided more in depth and valid assessments of teachers' and students' conceptions and have afforded the researcher a more contextual view of instructional sequence and the factors which mediate one's conceptions (Lederman, 1992).