Promoting preservice chemistry teachers' understanding about the nature of science through history

The purpose of this quasi‐experimental study was to document the benefits of teaching chemistry through history. The experimental group consisted of seniors enrolled in a teacher preparation program in which they learned how to teach chemistry through the history of science. Their understanding of the nature of science was compared with that of a control group, which consisted of juniors in the same department. The results of the analysis of covariance revealed that the experimental group outperformed the control group on an instrument documenting respondents' understanding of the nature of science. Additional frequency analysis and interview data indicated that the experimental group students had a better understanding of the nature of creativity, the theory‐based nature of scientific observations, and the functions of theories. In the pretreatment interviews, students in the experimental group based their explanations concerning the nature of science primarily on their intuition. In the posttreatment interview, however, they were able to explain their beliefs by using scientists' arguments or hypotheses as examples. This result indicates that the experimental group's understanding about the nature of science was enhanced by learning to teach through the history of science. © 2002 Wiley Periodicals, Inc. J Res Sci Teach 39: 773–792, 2002     

Exploring Conceptual Integration in Student Thinking: Evidence from a case study

Two reasons are suggested for studying the degree of conceptual integration in student thinking. The linking of new material to existing knowledge is an important aspect of meaningful learning. It is also argued that conceptual coherence is a characteristic of scientific knowledge and a criterion used in evaluating new theories. Appreciating this ‘scientific value’ should be one objective when students learn about the nature of science. These considerations imply that students should not only learn individual scientific models and principles, but should be taught to see how they are linked together. The present paper describes the use of an interview protocol designed to explore conceptual integration across two college‐level subjects (chemistry and physics). The novelty here is that a single interview is used to elicit explanations of a wide range of phenomena. The potential of this approach is demonstrated through an account of one student's scientific thinking, showing both how she applied fundamental ideas widely, and also where conceptual integration was lacking. The value and limitations of using this type of interview as one means for researching conceptual integration in students' thinking are discussed.     

What is the role of induction and deduction in reasoning and scientific inquiry?

A long‐standing and continuing controversy exists regarding the role of induction and deduction in reasoning and in scientific inquiry. Given the inherent difficulty in reconstructing reasoning patterns based on personal and historical accounts, evidence about the nature of human reasoning in scientific inquiry has been sought from a controlled experiment designed to identify the role played by enumerative induction and deduction in cognition as well as from the relatively new field of neural modeling. Both experimental results and the neurological models imply that induction across a limited set of observations plays no role in task performance and in reasoning. Therefore, support has been obtained for Popper's hypothesis that enumerative induction does not exist as a psychological process. Instead, people appear to process information in terms of increasingly abstract cycles of hypothetico‐deductive reasoning. Consequently, science instruction should provide students with opportunities to generate and test increasingly complex and abstract hypotheses and theories in a hypothetico‐deductive manner. In this way students can be expected to become increasingly conscious of their underlying hypothetico‐deductive thought processes, increasingly skilled in their application, and hence increasingly scientifically literate. © 2005 Wiley Periodicals, Inc. J Res Sci Teach     

Small groups' ecological reasoning while making an environmental management decision

The objective of this study was to explore the ideas and reasoning students use to make a collaborative environmental management decision. Eight groups of 8th‐grade students (n = 24) considered ecological and economic information about an invasive aquatic species to make a management recommendation. In addition to discussing the exact information they were given, the groups made a variety of interpretations, elaborations, and inferences concerning ecological structure and dynamics and practical aspects of the management scenario. Value judgments and concerns with uncertainty also appeared in students' discussions, to differing degrees. The students' discussions were compared with scientists' guidelines for making environmental management decisions, and with one expert's analysis of the particular management scenario the students considered. A major finding was that whereas across groups students touched on all of the themes that scientists consider to be important for making environmental management decisions, within most groups students focused more narrowly on particular themes, giving cursory treatment to other dimensions of the problem. The results point to a need to foster students' ecological background knowledge and integrative, systems thinking skills for making principled decisions about complex environmental issues. © 2002 Wiley Periodicals Inc. J Res Sci Teach 39: 341–368, 2002     

Investigating professed and enacted epistemic beliefs about the uncertainty of scientific knowledge when students evaluate scientific controversies

Prior research on epistemic beliefs, that is, individuals’ views about knowledge and knowing, has mainly focused either on individuals’ professed beliefs (as reported in questionnaires) or on their enacted beliefs (as indicated during task processing). However, little is known about the relation between professed and enacted epistemic beliefs. The present study focused on beliefs about the uncertainty of scientific knowledge and investigated both professed and enacted beliefs in the context of evaluations of scientific controversies. Participants were N = 79 university students who first completed a questionnaire that targeted their professed uncertainty beliefs about scientific knowledge. Then, approximately 1 week later, they completed a standardized test in which they evaluated five scientific controversies. Cued retrospective verbal reports were used to measure their enacted uncertainty beliefs while taking the test. Results revealed that professed and enacted uncertainty beliefs were interrelated and that both variables predicted individuals’ performance with regard to the evaluation of scientific controversies. Furthermore, the effect of professed uncertainty beliefs on controversy-evaluation performance was partly mediated by enacted uncertainty beliefs. The findings of the present study point toward novel theoretical insights and educational implications regarding the relations between professed and enacted beliefs about the uncertainty of scientific knowledge and their role in individuals’ evaluation of scientific controversies.

     

How some college students represent their understandings of the nature of scientific theories

This study explores college students' representations about the nature of theories during their enrollment in a large astronomy course with instruction designed to address a number of nature of science issues. We focus our investigation on how nine students represent their understanding of theory, how they distinguish between scientific theories and non‐scientific theories, and how they reason about specific theories. Students' notions of theory were classified under four main categories: (1) hypothesis, (2) idea with evidence, (3) explanation, and (4) explanation based on evidence. Students' condition for deciding whether a given idea is a scientific theory or not were classified under six criteria: content domain, convention, evidence, mathematical content, methodology, and tentativeness. Students expressed slight levels of variation between their reasoning about scientific theories in general and specific theories they learned in the course. Despite increased sophistication in some students' representations, this study affirms the complex dimensions involved in teaching and assessing student understanding about theories. The implications of this study underscore the need to explicitly address the nature of proof in science and issues of tentativeness and certainty students associate with scientific theories, and provide students with more opportunities to utilize the language of science.     

The Nature of Scientific Explanation: Examining the perceptions of the nature,quality, and “goodness” of explanation among college students,science teachers,and scientists

Issues regarding scientific explanation have been of interest to philosophers from Pre-Socratic times. The notion of scientific explanation is of interest not only to philosophers, but also to science educators as is clearly evident in the emphasis given to K-12 students' construction of explanations in current national science education reform efforts. Nonetheless, there is a dearth of research on conceptualizing explanation in science education. Using a philosophically guided framework—the Nature of Scientific Explanation (NOSE) framework—the study aims to elucidate and compare college freshmen science students', secondary science teachers', and practicing scientists' scientific explanations and their views of scientific explanations. In particular, this study aims to: (1) analyze students', teachers', and scientists' scientific explanations; (2) explore the nuances about how freshman students, science teachers, and practicing scientists construct explanations; and (3) elucidate the criteria that participants use in analyzing scientific explanations. In two separate interviews, participants first constructed explanations of everyday scientific phenomena and then provided feedback on the explanations constructed by other participants. Major findings showed that, when analyzed using NOSE framework, participant scientists did significantly “better” than teachers and students. Our analysis revealed that scientists, teachers, and students share a lot of similarities in how they construct their explanations in science. However, they differ in some key dimensions. The present study highlighted the need articulated by many researchers in science education to understand additional aspects specific to scientific explanation. The present findings provide an initial analytical framework for examining students' and science teachers' scientific explanations.     

Science curriculum and teacher education: The role of presuppositions,contradictions, controversies and speculations vs Kuhn's ‘normal science’

Kuhn (1970) considered textbooks to be good 'pedagogical vehicles' for the perpetuation of ‘normal science’. Collins (2000) has pointed out a fundamental contradiction with respect to what science could achieve (create new knowledge) and how we teach science (authoritarian). Despite the reform efforts, students still have naïve views about the nature of science. Textbook analyses show almost a complete lack of understanding of the role played by presuppositions, contradictions, controversies and speculations in scientific progress. A possible solution to the contradiction pointed out by Collins is provided by the comparison of teaching approaches based on Kuhnian and Lakatosian perspectives of history and philosophy of science. It appears that the Kuhnian approach leaves out what really happens, that is the 'how' and 'why' of scientific progress. On the other hand, the Lakatosian perspective would enable students to understand that scientific progress is subsumed by a process that involves conflicting frameworks (dispute in science, according to Collins, 2000), based on processes that require the elaboration of rival hypotheses and their evaluation in the light of new evidence. It is plausible to suggest that the teacher by 'unfolding' the different episodes (based on historical reconstructions) can emphasize and illustrate how science actually works (tentative, controversial, rivalries, alternative interpretations of the same data), and this will show to the students that they need to go beyond ‘normal science’ as presented in their textbooks.     

Making authentic science accessible to students

Authentic activities are important in promoting inquiry because they provide natural problem-solving contexts with high degrees of complexity. This study designed and studied effective inquiry tasks through transforming content, scientific thinking, and resources featured in scientists' authentic practices. This study investigated how 59 inner-city 6th grade students performed in real-time forecasting situations involving fronts and pressure systems. Forecasts were evaluated in terms of prediction agreement, meteorological entity consideration, explanation type, and scientific knowledge use because these four categories reflected inquiry features emphasized in the forecasting task. Results show that real-world situations that mapped closely onto students' content understandings, rather than those with naturally occurring complex patterns, helped students perform inquiry. Key ideas discussed in this paper include the importance of using authentic situations to develop rich understandings about scientific knowledge and the design of tasks that prepare students to participate in social practices valued by the science community.     

Re-negotiating the discourse of lower track high school students

The purpose of this study was to examine how lower track science students would understand shifts in standard classroom discourse patterns. The researcher videotaped his daily efforts to renegotiate the lower track classroom environment to become more representative of a scientific community. This paper is an analysis of the implicit obstacles inherent in shifting class discussions to classroom arguments examining tentative hypotheses. Students have inserted struggles for social status into classroom arguments about scientific ideas making it difficult to separate in a group discussion when the evidence convinced a student or whether the social politics of the class had persuaded her. As a result of changing classroom rules for participation, engagement, and collaborative inquiry, students' abilities to argue scientifically were changed. Despite these shifts students continued to insert their own interpretations of argumentation, social norms, and strategies for active re-negotiation of the teacher's agenda for the construction of scientific classroom discourse.     

The glue that makes it “hang together”: A framework for identifying how metadiscourse facilitates uncertainty navigation during knowledge building discussions

Classroom discussions have become a centerpiece of reform efforts in science education because talk mediates the joint co-constructing of knowledge in science classrooms. Although decades of research underscore the importance of talk in supporting science learning, the science education community continues to grapple with how to support teachers and students in navigating the uncertainty that is associated with doing knowledge building work. To address these challenges, we must examine not just what gets constructed (the scientific ideas), but how knowledge is co-constructed by teachers and students (the process of building those ideas) amidst uncertainty. In this study, we propose a conceptual tool for identifying organizational, epistemic, and interpretive metadiscourse markers (MDMs) in science talk. We highlight how teachers and students use these three types of MDMs as they navigate uncertainty while connecting ideas within and across multiple turns of talk, leveraging resources for knowledge building, and making interpretations about one another's ideas. We conclude with a set of suggestions for how researchers and teachers can utilize this framework to attend to the ways that MDMs index the organizational, epistemic, and interpretive dimensions of uncertainty in the knowledge building process.     

Connections between Student Explanations and Arguments from Evidence about Plant Growth

We investigate how students connect explanations and arguments from evidence about plant growth and metabolism—two key practices described by the Next Generation Science Standards. This study reports analyses of interviews with 22 middle and high school students postinstruction, focusing on how their sense-making strategies led them to interpret—or misinterpret—scientific explanations and arguments from evidence. The principles of conservation of matter and energy can provide a framework for making sense of phenomena, but our results show that some students reasoned about plant growth as an action enabled by water, air, sunlight, and soil rather than a process of matter and energy transformation. These students reinterpreted the hypotheses and results of standard investigations of plant growth, such as van Helmont''s experiment, to match their own understanding of how plants grow. Only the more advanced students consistently interpreted mass changes in plants or soil as evidence of movement of matter. We also observed that a higher degree of scaffolding during some of the interview questions allowed mid-level students to improve their responses. We describe our progress and challenges developing teaching materials with scaffolding to improve students’ understanding of plant growth and metabolism.     

Students' Visualization of Diagrams Representing the Human Circulatory System: The use of spatial isomorphism and representational conventions

This study investigated students' interpretation of diagrams representing the human circulatory system. We conducted an interview study with three students aged 14–15 (Year 10) who were studying biology in a Hong Kong school. During the interviews, students were asked to interpret diagrams and relationships between diagrams that represented aspects of the circulatory system. All diagrams used in the interviews had been used by their teacher when teaching the topic. Students' interpretations were expressed by their verbal response and their drawing. Dual coding theory was used to interpret students' responses. There was evidence that one student relied on verbal recall as a strategy in interpreting diagrams. It was found that students might have relied unduly on similarities in spatial features, rather than on deeper meanings represented by conventions, of diagrams when they associated diagrams that represented different aspects of the circulatory system. A pattern of students' understanding of structure–behaviour–function relationship of the biological system was observed. This study suggests the importance of a consistent diagrammatic and verbal representation in communicating scientific ideas. Implications for teaching practice that facilitates learning with diagrams and address students' undue focus on spatial features of diagrams are discussed.     

Reconceptualizing Elementary Teacher Preparation: A case for informal science education

The purpose of this case study was to explore the ways in which 3 different informal science experiences in the context of an elementary methods course influenced a group of prospective elementary teachers' ideas about science teaching and learning as well as their understandings about the role of informal science environments to teaching and learning. In order to address this question, data were collected in a period of an academic semester through the following sources: journal entries for each of the 3 experiences, a personal teaching philosophy statement and a 2-hour long semi-structured interview with each of the 12 participants. Open coding techniques were used to analyze the data in order to construct categories and subcategories and eventually to identify emerging themes. The outcomes of the analysis showed that the inclusion of informal science experiences in the context of teacher preparation has the potential to support beginning elementary teachers' development of contemporary ideas about science teaching and learning related to inquiry-based science, the nature of scientific work and the work of scientists, connecting science with everyday life, and making science fun and personally meaningful. These findings are discussed alongside implications for policy, teacher preparation, and research under these themes: (a) addressing reform recommendations; (b) developing positive orientations toward science and science teaching; and (c) constructing understandings about scientists' work.     

Lasting effects of instruction guided by the conflict map: Experimental study of learning about the causes of the seasons

This study was based on the framework of the “conflict map” to facilitate student conceptual learning about causes of the seasons. Instruction guided by the conflict map emphasizes not only the use of discrepant events, but also the resolution of conflict between students' alternative conceptions and scientific conceptions, using critical events or explanations and relevant perceptions and conceptions that explicate the scientific conceptions. Two ninth grade science classes in Taiwan participated in this quasi‐experimental study in which one class was assigned to a traditional teaching group and the other class was assigned to a conflict map instruction treatment. Students' ideas were gathered through three interviews: the first was conducted 1 week after the instruction; the second 2 months afterward; and the third at 8 months after the treatment. Through an analysis of students' interview responses, it was revealed that many students, even after instruction, had a common alternative conception that seasons were determined by the earth's distance to the sun. However, the instruction guided by the framework of the conflict map was shown to be a potential way of changing the alternative conception and acquiring scientific understandings, especially in light of long‐term observations. A detailed analysis of students' ideas across the interviews also strongly suggests that researchers as well as practicing teachers need to pay particular attention to those students who can simply recall the scientific fact without deep thinking, as these students may learn science through rote memorization and soon regress to alternative conceptions after science instruction. © 2005 Wiley Periodicals, Inc. J Res Sci Teach 42: 1089–1111, 2005     

Level I and level II: A review

Jensen's Level I‐Level II theory of individual and group differences in mental abilities is examined in the context of the large body of research pertaining to the topic. The major hypotheses of Jensen's theory, concerning the equal distribution of Level I abilities among different racial and sociocconomic groups, and the differences in the distribution of Level II abilities are evaluated. It is concluded that the majority of recent research supports Jensen's hypotheses. Alternative theories to Jensen's arc presented and the implications of Jensen's theory for the education of disadvantaged and low Level II children arc discussed. A short section deals with the hypothesized functional relationship between Levels I and II.