Exploring alternative approaches to methodology in educational research

The objective of this study is to provide in-service teachers an opportunity to become familiar with the controversial nature of progress in science (growth of knowledge) and its implications for research methodology in education. The study is based on 41 participants who had registered for a nine-week course on Methodology of Investigation in Education, as part of their Master’s degree program. The course is based on 20 readings drawing upon a history and philosophy of science perspective (positivism, constructivism, Popper, Kuhn, Lakatos) and its implications for educational research. Course activities included written reports, class room discussions based on participants’ presentations, and written exams. Based on the results obtained it was concluded that: (a) participants were able to understand the basic ideas of constructivist philosophy and its pedagogical implications; (b) the role of behavioural objectives in actual educational practice was questioned; (c) integration of qualitative and quantitative research methods was considered to be an alternative to the current debate about the replacement of one method by the other; (d) participants considered the dilemma of evaluating students based on what they have learned or what they should have learned, within the social constructivist framework and generally favoured the former; and (e) most of the participants were reluctant to accept constructivism as a form of positivism, a controversial thesis that is gaining support in the research literature. Given the importance of alternative approaches to growth and meaning of knowledge, it is important that teachers be aware of conflicting situations in the classroom that refer to: objectivity, scientific method, qualitative-quantitative methods, relationship between method and problem, evaluation, and a critical appreciation of constructivism.     

Understanding divergent domestication traits from the whole-genome sequencing of swamp- and river-buffalo populations

Domesticated buffaloes have been integral to rice-paddy agro-ecosystems for millennia, yet relatively little is known about the buffalo genomics. Here, we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals (132 swamp buffaloes and 98 river buffaloes) sampled from across Asia and Europe. Beyond the many actionable insights that our study revealed about the domestication, basic physiology and breeding of buffalo, we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior, digestion metabolism, strengths and milk production.     

A Conceptual Change Teaching Strategy to Facilitate High School Students' Understanding of Electrochemistry

Recent research in chemistry education has shown an increasing interest in the facilitation of conceptual change in student understanding of chemical concepts. Most of the studies have tried to show the difference in student performance on algorithmic and conceptual problems. The objective of this study is to go beyond and design a teaching strategy based on two teaching experiments that could facilitate students' conceptual understanding of electrochemistry. The study is based on two sections (control, n = 29; experimental, n = 28) of 10th grade high school students at a public school in Venezuela. Experimental group participated in two teaching experiments designed to generate situations/experiences in which students are forced to grapple with alternative responses leading to cognitive conflicts/contradictions. Results obtained show that learning electrochemistry involves both algorithmic and conceptual problems. On Posttest 1, 93% of the experimental group students responded correctly, in contrast to 39% of the control group. On Posttest 2, 39% of the experimental group responded correctly, in contrast to 0% of the Control group. The difference in performance on both posttests is statistically significant (p < 0.001). It is concluded that the teaching experiments facilitated students' understanding (progressive transitions) of electrochemistry.     

Baroque Tower on a Gothic Base: A Lakatosian Reconstruction of Students' and Teachers' Understanding of Structure of the Atom

The main objective of this study is a reconstruction of students' and teachers' understanding of structure of the atom based on the following framework: a) history of science can be conceived as that of competing rival research programs; b) some of the greatest scientific research programs progressed on inconsistent foundations; c) in actual scientific practice, counter-examples would be considered as mere anomalies; d) work of Thomson, Rutherford and Bohr led to the postulation of atomic models based on competing frameworks of understanding. This study is based on 171 freshman students enrolled in General Chemistry I and 7 chemistry teachers at the Instituto Universitario de Tecnología, El Tigre, Venezuela. All the students and teachers were asked to respond to a 11 item questionnaire and explain their responses. The questionnaire was administered about a month after the students/teachers had finished the topic of atomic structure. Students' and teachers' responses were classified in the following categories: Positivist/inductivist, Transitional and Lakatosian. Results obtained show that students and teachers: a) have a very similar positivist understanding of the progress of science; b) are inconsistent in their responses by switching from a positivist response on one item to a Lakatosian on an another; c) also showed some consistent response patterns by resisting changes in some of their core beliefs by invoking "auxiliary hypotheses"; and d) consider that observable hard experimental facts give science its objective status, whereas the interpretations being subjective perhaps go beyond the fold of science.     

Translation of algebraic equations and its relation to formal operational reasoning

A large proportion of science major college students are unable to translate even simple sentences into algebraic equations. Given the following sentence: There are six times as many students (S) as professors (P) at this university, most students write the following equation: 6S = P, referred to as the reversal error. In order to overcome the reversal error students need to operate in a hypothetico-deductive manner, i.e., performing a hypothetical operation that makes the group of professors six times larger than it really is (S = 6P). The objective of this study is to investigate the relation between student ability to translate sentences into equations, equations into sentences, and student performance in the following variables: formal operational reasoning, proportional reasoning, and introductory freshmen-level chemistry course. The results obtained show that as the student ability to translate sentences into equations and equations into sentences increases, their mean scores in Chemistry I, formal operational, and proportional reasoning increases. This study has found support for the hypothesis that students who lack formal operational reasoning skills (hypothetico-deductive reasoning) may experience more problems in the translation of algebraic equations.     

Contents of Volume 28 2000

Volume Contents

Contents of Volume 28 2000     

The Oil Drop Experiment: A Rational Reconstruction of the Millikan–Ehrenhaft Controversy and Its Implications for Chemistry Textbooks

Research in science education has recognized the importance of history and philosophy of science. Given this perspective, it is important to analyze how general chemistry textbooks interpret Millikan's oil drop experiment. This study has the following objectives: (a) elaboration of a history and philosophy of science framework based on a rational reconstruction of experimental observations that led to the Millikan–Ehrenhaft controversy; (b) formulation of six criteria based on the framework, which could be useful in the evaluation of chemistry textbooks; and (c) evaluation of 31 chemistry textbooks based on the criteria. Results obtained showed that most textbooks lacked a history and philosophy of science framework and did not deal adequately with the following aspects. (a) The Millikan–Ehrenhaft controversy can open a new window for students, demonstrating how two well‐trained scientists can interpret the same set of data in two different ways. (b) Millikan's perseverance with his guiding assumption shows how scientists can overcome difficulties with anomalous data. (c) Millikan's methodology illustrates what modern philosophers of science consider important issues of falsification, confirmation, and suspension of disbelief. (d) The experiment is difficult to perform even today, owing to the incidence of a series of variables. (e) Millikan's major contribution consists of discovering the experiment to provide confirmation for the elementary electrical charge. © 2000 John Wiley & Sons, Inc. J Res Sci Teach, 37: 480–508, 2000.     

Balancing chemical equations: The role of developmental level and mental capacity

Why are some students able to learn to use the trial and error method to balance chemical equations while others are not? To test the hypothesis that formal reasoning is required to balance even simple one-step equations, while formal reasoning and a sufficiently large mental capacity are required to balance more complex many-step equations, a sample of science students was tested to determine level of intellectual development, mental capacity, and degree of field dependence/field independence. Students were then given classroom instruction in using trial and error to balance equations. As predicted, a posttest revealed significant correlations between developmental level and equation balancing ability for both simple and complex equations. Also, as predicted, mental capacity correlated significantly with complex equations but not with simple equations. Field dependence/field independence played no significant role in performance. Educational implications are drawn.     

A rational reconstruction of the origin of the covalent bond and its implications for general chemistry textbooks

The main objectives of this study are: (i) development of a perspective based on history and philosophy of science considerations (rational reconstruction) in order to understand the postulation of the covalent bond by Lewis; (ii) formulation of four criteria based on the perspective; and (iii) evaluation of 27 textbooks based on the four criteria. Results obtained show that most textbooks lacked a history and philosophy of science perspective and did not deal adequately with the following aspects: (i) Lewis's postulation of the covalent bond in 1916 posed considerable conceptual difficulties; (ii) Lewis used the cubical atom (a hypothetical entity) in order to understand the sharing of electrons in the covalent bond (octet rule); (iii) sharing of electrons had to compete with the transfer of electrons (ionic bond) considered to be the dominant paradigm until about 1920; (iv) postulation of the covalent bond (octet rule) was not an inductive generalization based on stability of the noble gases and the high dissociation energy of the covalent bonds; and (v) Pauli exclusion principle provides a theoretical explanation of the sharing of electrons, just as the cubical atom did previously. It is concluded that the development of the covalent bond does not follow the inductivist process, viz. experimental observations lead to scientific laws which later facilitate the elaboration of explanatory theories.     

Gases as Idealized Lattices: A Rational Reconstruction of Students' Understanding of the Behavior of Gases

The main objective of this study is to establish a relationship between students' understanding of gases and its parallels in the history of science (rational reconstruction). Fifty-nine freshman students were asked to respond to a gas problem that did not require any calculations but rather conceptual understanding (due to molecular collisions, gases occupy all the available space). Before responding to the problem students were exposed to an elementary version of the kinetic theory of gases. Results obtained showed that a large proportion of the students gave explanations that approximate quite closely to an idealized form of the Lattice Theory of Gases. This theory considered molecules in gases to be arranged in the form of regular lattices, rather as if gases were highly expanded solids, and was held by most chemists until about 1860. It is concluded that some of the students' alternative conceptions about gas behavior (attractive forces between gas molecules increase as the temperature decreases) are resistant to change and recapitulate theories scientists held in the past.