Historians of science are as much interested in teaching about a "chronology" of scientific discoveries, as science educators are interested in teaching about scientific "facts." Historians of science and science educators are much more interested in helping learners develop some understandings about science, about the workings of the scientific endeavor, about nature of science (NOS). Indeed, using history of science (HOS) to teach about "the meaning of science, its function, its methods, its logical, psychological and social implications" has been central to the efforts of historians of science (Sarton, 1952, p. 59). Similarly, helping learners develop informed views of NOS is the single most advocated and long-lived goal for science education. The longevity of this goal has only been surpassed by studentsŐ and science teachersŐ inability to articulate informed views of NOS.

During the past 70 years science educators have repeatedly argued that HOS can play a significant role in furthering students' and teachers' understandings of NOS, and many advanced that science-teacher preparation should include coursework in HOS. However, despite their longevity, these arguments seem to be solely based on intuitive assumptions and anecdotal evidence: no empirical research in the science education literature has examined the influence of college level HOS courses on learners' NOS views (Abd-El-Khalick & Lederman, in press).

Additionally, science educators seem to have overlooked the conceptual difficulties associated with using history to learn about NOS. Such difficulties were long recognized by historians and given different labels such as, "putting on a different kind of thinking cap" (Butterfield, 1965, p. 1) or "recapturing out-of-date ways of reading out-of-date texts" (Kuhn, 1977, p. xiii). Historians recognize that to discern "lessons" about science from history, learners should not "read" or indiscriminately judge historical materials from within the spectacles of present scientific ideas or practices. Otherwise, subtleties of the historical narrative are likely to be lost and "lessons" about NOS disregarded. Rather, when interpreting historical materials, learners need to disregard their assumptions and conceptions, and situate themselves in the "scientific," social, and cultural contexts of the historical period under study. Next, learners need to "step back to the future" and discern the relevance of the lessons learned to understanding the nature of current scientific assumptions, values, and practices.

Nonetheless, getting learners to "step out of their shoes" while examining historical narratives would prove much more difficult and complex than what historians might anticipate. Learning theories and research in science education indicate that (a) learners make sense of their experiences from within personal ideas they bring into learning environments, (b) learnersŐ ideas are usually entrenched and survive formal traditional instruction, and (c) often, these ideas are at odds with, and impede internalizing more accurate disciplinary conceptions. An extended line of research in science education indicates that it is highly likely that learners would join HOS courses with a host of entrenched misconceptions about NOS (Abd-El-Khalick & Lederman, in press), and consequently interpret historical materials from within such misconceived notions, let alone abandoning their views and adopting alternate frameworks that are radically different from their own.

The need to "put on a different kind of thinking cap" while examining HOS and the difficulties associated with achieving such a conceptual shift might seriously compromise the effectiveness of a historical approach in helping learners enrolled in one or a few HOS courses develop more informed NOS views. One possible way to overcome this difficulty is to provide learners with a conceptual framework consistent with current views of NOS prior to their enrollment in HOS courses. Such framework might provide learners with an alternate way of reading HOS, thus increasing the likelihood of them discerning target NOS ideas and enriching their understandings of these ideas with relevant examples or "stories." With these ideas in mind, findings from an empirical investigation (Abd-El-Khalick & Lederman, in press) that assessed the influence of HOS courses on college students' NOS views are summarized next.

Participants were all 171 undergraduate and graduate students enrolled in three HOS courses offered in a mid-sized Western state university. Ten participants were preservice secondary science teachers and had received explicit activity-based NOS instruction in a science methods course prior to their enrollment in one of the participant HOS courses. One HOS course (the "Controversy" course) used case studies of controversial scientific discoveries to highlight the rational, psychological, and social characteristics that typify the natural sciences. Another course (the "Survey" course) surveyed the period from ancient civilization to the post-Roman era focusing on the interaction of scientific ideas with their social and cultural contexts. The third course (the "Evolution" course) explored the origin, development, and reception of DarwinŐs evolutionary theory from its inception to the present.

During the first and last weeks of each course participants were administered an open-ended questionnaire intended to assess their NOS views. Each questionnaire administration was coupled with follow-up individual interviews with a 20% random sample of participants. The HOS course professors were also interviewed to generate profiles of their course objectives, priorities, and historical and teaching approaches. Additionally, the researcher sat through the courses, audio-taped all course sessions, and kept detailed field notes to document instances where NOS aspects were addressed. Data were qualitatively analyzed and systematically compared to assess changes in participantsŐ NOS views.

At the beginning of the study the greater majority of participants held na•ve views of several aspects of NOS. These aspects included the tentative, empirical, creative, inferential, and theory-laden NOS; the functions of, and relationship between scientific theories and laws; the aim and structure of scientific experiments; and the logic of hypothesis and theory testing. For example, a majority of participants believed that scientific knowledge was certain, that theories become elevated to the status of "law" when they are "proven correct," and that scientific theories are non-substantiated opinions.

At the conclusion of the study change was evident in the views of as little as 16%, 17%, and 31% of the Survey, Controversy, and Evolution course participants respectively. Moreover, of nine NOS aspects explored in the study, almost all the observed changes in individual participantsŐ conceptions were related to only one aspect of NOS or another. Change was evident in the views of relatively more participants who entered the HOS courses with more informed views of NOS. Indeed, the percentage of these latter participants whose views have changed is twice as large as the corresponding percentage among participants who entered the HOS courses with relatively less informed NOS views. Additionally, of the 10 participant preservice teachers, the views of eight were influenced. The reader is reminded that these preservice teachers received some explicit NOS instruction prior to their enrollment in the Evolution course.

Almost all of the changes that were evident in participants' NOS views could be directly related to those NOS aspects that were explicitly addressed in the respective HOS courses, as compared to ones embedded in the historical narrative. The Evolution course, which was relatively more effective in influencing participantsŐ views, featured more explicit attention to certain NOS aspects and explicit attempts to help participantsŐ approach the historical materials from within frameworks that were more consistent with the relevant historical period. Moreover, of the participant HOS courses attributes that could account for the observed results, besides explicit attention given to NOS, the most likely ones were course objectives and instructor priorities. The Evolution course professor articulated an explicit commitment to helping students develop more informed NOS views. The Survey and Controversy course professors did not explicitly express a similar commitment.

The relatively limited influence that the participant HOS courses had on learnersŐ NOS views does not lend empirical support to the intuitively appealing assumption held by many science educators and probably many historians of science that coursework in HOS would necessarily promote student understandings of NOS. The present results indicate that if historians of science aim to enhance students' NOS views, then an explicit (which should not be mistakenly equated with a didactic) instructional approach that targets certain NOS aspects can be more effective than an implicit approach in which lessons about NOS are embedded in or implied by the historical narrative. Historians of science need to explicitly guide students in the process of interpreting historical narratives from within alternative perspectives. Students also should be explicitly helped to discern relationships between any generalizations derived from the historical narrative and the nature of current scientific knowledge and practices given the well documented limited ability of learners to transfer acquired understandings from one context to another (Gage & Berliner, 1998).

However, an explicit approach might not suffice to substantially change students' entrenched misconceptions of NOS. For even though an explicit approach generated relatively more change in participantsŐ views (as was the case with the Evolution course), much is still desired. A conceptual change approach (Posner, Srike, Hewson, & Gertzog, 1982) might be more effective. In the context of HOS courses, such an approach entails several stages. StudentsŐ views of certain NOS aspects are first elicited. Next, specific historical examples are used to help students discern the inadequacy of, and raise their dissatisfaction with some of their current NOS conceptions. Students are then explicitly presented with more adequate and plausible conceptions of the target NOS aspects. The historical narrative can then be employed to provide students with opportunities to perceive the applicability and fruitfulness of these newly articulated views in making sense of various aspects of scientific knowledge and practice in a variety of historical and disciplinary contexts. A conceptual change approach, it should be emphasized, is time consuming and demands a specific commitment on the part of HOS course instructors to enhance studentsŐ views of NOS probably at the expense of other instructional objectives.

Finally, it is noteworthy that despite an extended and mutual interest on the part of historians of science and science educators in helping learners develop informed NOS views, the two communitiesŐ efforts to achieve this valued educational goal have been largely mutually exclusive. There are significant experiences, expertise, and lessons to be shared and much could be learned and achieved from discourse and collaboration between the two communities. The above results, for example, indicate that it might be fruitful and effective for purposes of enhancing prospective science teachersŐ NOS views to initiate collaborative efforts whereby specific NOS aspects explicitly emphasized in the context of teacher education courses are reinforced, elaborated, and enriched within the context of HOS courses through historical narratives explicitly geared toward that end.

This is an open invitation for discourse and collaboration with historians of science interested in enhancing learnersŐ NOS views. In the very least, such discourse could help make historians of science and science educators more cogent of each othersŐ priorities, needs, and goals, thus initiating collaborative efforts that would further our understanding of ways to foster informed conceptions of one of the most interesting and successful enterprises of the human endeavor, science.

References

Abd-El-Khalick, F., & Lederman, N. G. (in press). "The influence of history of science courses on studentsŐ views of nature of science." Journal of Research in Science Teaching.

Butterfield, H. (1965). The Origins of Modern Science, 1300-1800. New York: Free Press. Gage, N. L., & Berliner, D. C. (1998). Educational psychology (6th ed.). Princeton, NJ: Houghton Mifflin.

Kuhn, T. S. (1977). The essential tension: Selected studies in scientific tradition and change. Chicago: The University of Chicago Press.

Posner, G., Srike, K., Hewson, P., & Gertzog, W. (1982). "Accommodation of a scientific conception: Toward a theory of conceptual change." Science Education, 66, 211-227.

Sarton, G. (1952). A guide to the history of science. New York: Ronald Press.