Chemical Education Today
Reports from Other Journals
Hidden Insights in the Science Education Research Literature by William R. Robinson
Research in science education, like research in other sciences, is a stepwise process. The results can provide immediate insights, or their utility may not be immediately apparent. Sometimes we find results that also inform an unexpected and apparently unrelated area. Such is a study reported by M. Gail Jones, Glenda Carter, and Melissa J. Rua in their paper, “Exploring the Development of Conceptual Ecologies: Communities of Concepts Related to Convection and Heat” (1). This report is one that helps us understand the influences of family and cultural experiences (such as religious beliefs, weather, and airplanes) on conceptual development and the extent to which competing phenomena (such as evaporation and dissolving) effect the development of new conceptual understandings, be these understandings appropriate or not. But it also informs us in an area that its title does not imply, and it is this latter insight that may be of interest to most readers of this Journal. By conceptual ecology the authors mean “a student’s knowledge of a particular domain including the rich tangle of connections to prior experiences and understandings.” Within a conceptual ecology there are numerous communities of concepts (sometimes called schemas). For example, in a chemist’s conceptual ecology of heat, we probably would find a community of concepts associated with summer, another associated with macroscopic behavior such as phase change, another associated with the kinetic-molecular theory, among others. The community of concepts used to make sense of a particular event or series of related events is invoked by an individual’s interpretive framework. This framework reflects an individual’s points of view, belief systems, and knowledge sets; it influences the operation of various mental processes, including the activation of a community of concepts. Jones, Carter, and Rua examined the relationship and development of students’ communities of concepts related to convection. The study involved fifth grade students who worked in pairs for a series of three laboratory investigations. During the first two investigations, students conducted a series of activities that required them to make detailed observations of convection currents in water. They were also directed to answer questions about their observations on laboratory record sheets. During the third investigation they observed convection currents in air and worked together to answer questions about the similarities and differences they had observed for the currents in air and in water. The experiments included activities such as observing the motion of food coloring dropped into a cup of hot water and the shadows cast by the gases of a candle flame or the hot air rising from a hot plate. The dialog of selected pairs of students was recorded during their lab work and the pairs were observed by one of the researchers. Student knowledge was assessed before and after instruction using written tests, student-generated concept maps, and interviews involving diagrams and card-sort 556
tasks. During a cardIt follows from these sort task, students were given 20 cards, each containing a observations that reliance on term common to heat, a single mode of assessing and they were asked to sort the cards into our students’ learning can piles according to the way they believed the lead to a restricted view of words were related. Then they were asked what they truly know. to explain the reasons for their sorting. It was observed that students’ conceptual ecologies are very complicated and complex. There were commonalities and patterns in their interpretive frameworks, but there were also context-dependent and diverse variations as well as idiosyncratic applications of prior experiences. Among the common features observed among students in this study were their invocations of an anthropomorphic intent or causal agent, their use of evaporation to explain the rise of hot air, their use of dissolving to interpret the motion of food coloring in convection currents, and their use of analogies and examples to “make the unfamiliar familiar”. Some examples follow. In their discussions, students commonly gave heat an active drive or intent by attributing characteristics normally attributable to humans or other animals. The statement “It tried to get close to the cold water at the bottom” is an example of anthropomorphization. Students who attribute the behavior to causation invoke an agent that has a purposeful goal for the entity it acts on—for example, “…the cool air attracts the hot air.” Students commonly attribute convective effects to evaporation. When describing the hot air rising from a city, one student remarked, “Some air is evaporating”, although some also recognize that evaporation does not fully explain the observations. The perhaps unexpected information contained in this report is summarized in the authors’ statement, “Each assessment measure elicited different types of knowledge.” Concept maps were effective in discovering the materials, conditions, and behaviors that students associate with the concept of heat. Card-sorting interviews elicited declarative knowledge (statements). Diagrams provoked responses that provided insights into students’ thinking about heat and convection and the prior experiences that shaped their thinking. Transcripts of interviews and of discussions between students as they worked with diagrams or experiments provided information on the sequencing and evolution of their ideas. Clearly, these different techniques assess different types of knowledge or understanding. One interpretation of these observations is that verbal assessment (such as card-sorts and written tests) and visual assessment (such as diagrams and experiments) draw on different communities of concepts that
Journal of Chemical Education • Vol. 77 No. 5 May 2000 • JChemEd.chem.wisc.edu
Chemical Education Today
exist within a student’s conceptual ecology. It follows from these observations that reliance on a single mode of assessing our students’ learning can lead to a restricted view of what they truly know. It is interesting that the paper following the Jones, Carter, and Rua report also speaks about assessment. In their paper, “Identification and Analysis of Student Conceptions Used to Solve Equilibrium Problems”, Kirk W. Voska and Henry W. Heikkinen report the results of their development and testing of a 10-item, two-tier assessment instrument designed to diagnose misconceptions associated with the application of Le Châtelier’s principle (2). A two-tier item asks a question as the first part of the item. Then, in the second part of the item, it asks for the reason for the answer to the first part. Analysis of student success rates showed that students who provide correct reasons on a two-tier test have a higher rate of success in identifying the answer to the question. As part
of their report, the authors suggest that instructors should construct assessment items that probe student understanding, rather than just the students’ ability to identify correct or incorrect answers. They also conclude that conventional multiple choice tests that do not probe students’ reasoning are not adequate for investigating students’ understanding of a subject. Literature Cited 1. Jones, M. G.; Carter, G.; Rua, M. J. J. Res. Sci. Teach. 2000, 37, 139–159. 2. Voska, K. W.; Heikkinen, H. W. J. Res. Sci. Teach. 2000, 37, 160–176.
William R. Robinson is in the Department of Chemistry, Purdue University, West Lafayette, IN 47907; wrrobin@ purdue.edu
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