Chemical Education Today
Reports
A View of the Science Education Research Literature by William R. Robinson imposed by their school population. All three were seniors What can a science education research study in a biolat a university high school, students only 3 to 12 months ogy classroom tell us about teaching chemistry? A great deal, removed from college-level introductory courses. Their because it sheds light on how students learn. One of our jobs study of evolutionary theory inas chemistry teachers and faculty is volved no math or statistics. Inhelping students change their minds about the nature of matter and develop The study also reminds us that chang- stead, they studied a qualitative treatment of the historical developappropriate ideas about the microscopic ing minds so students accept new ment of the theory, evidence for evoworld and other models of chemical belution, evolutionary relationships, havior. The report “Patterns of Concep- ideas can be a slow process… patterns of evolution, and aspects of tual Change in Evolution” by Sherry S. evolutionary explanations. Demastes, Ronald G. Good, and Patsye Peebles, published The report identifies four modes of conceptual change in the Journal of Research in Science Teaching, 1996, 33, in the students studied, two of which are congruent with 407–431, describes a study of three students as their conthe conceptual change model proposed by Posner et al. cepts of the theoretical framework of biological evolution (Science Education, 1982, 66, 211–226) and two others sugchange during their second year of high school biology. gesting that additional modes of conceptual restructuring The course used evolution as a unifying theme. Evoluoccur. The conceptual change model suggests that the contion was taught as a distinct unit as well as integrated cepts we use to help organize our understanding of the throughout the course. Like the qualitative basics of the world can only be replaced by new concepts if a new conkinetic–molecular theory, the theoretical framework of cept (say, for example, a particle theory of matter, or natubiological evolution is relatively simple: ral selection) is judged to be plausible, more intelligible, and 1. Individuals in a population of any species vary in more fruitful than its predecessor (for example, a continumany heritable traits. ous model of matter, or a “need-to-change” model of evolu2. Those individuals with traits best suited to the local tion). According to the model, an individual conceptual environment generally leave a disproportionately change can be wholesale, with a new concept replacing the large number of surviving offspring; thus, these traits old concept, or can be gradual, with the new concept evolvappear in larger numbers in successive generations. ing from the old one. Natural selection is the editing process that selects This study documents two additional modes of change individuals with heritable features that favor their that occurred over the course of the year: a cascading reproductive success. change, during which a change in one conception allowed a The research employed a qualitative design. Each stusequence of conceptual changes to occur, and a dual condent participated in a series of 17 structured and openstruction, during which students constructed two logically ended interviews spread throughout the school year. The incompatible conceptions without recognizing the inconsisinterview questions were developed using reports of altertency. The study also reminds us that changing minds so nate conceptions (misconceptions) about evolution from the students accept new ideas can be a slow process, even literature. Concepts and changes in concepts were identithough the change appears simple to those of us who have fied as each of the three researchers reviewed transcripts already made that change. of the interviews, notes from classroom observations, and examinations and other written work. William R. Robinson is in the Department of ChemisThe student participants were selected using a purtry, Purdue University, West Lafayette, IN 47907; poseful sampling designed to provide the widest possible
[email protected]. diversity in content knowledge, given the limitations
Vol. 74 No. 11 November 1997 • Journal of Chemical Education
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