Stability and lability in student conceptions:
some evidence from a case study.
Presentation at BERA, Liverpool, 1993
Stability and lability in student conceptions:
some evidence from a case study.
Keith S. Taber
Paper presented at the British Educational Research Association Annual Conference, University of Liverpool, September1993
Abstract.
Educational research from recent years (constructivism, stage theories, and ‘alternative conceptions’ work) inform us that the classroom teacher needs to be able to answer key questions before embarking on the teaching of a topic:
“What do the students already ‘know’ about this topic?”
“How consistent is the ‘prior knowledge’ with what I wish to teach?”
“What level of sophistication of ideas are the students ready to deal with in this topic?”
“How difficult will it be to overcome resistance due to any “students’ knowledge” that is inconsistent with the “expert knowledge” I am trying to teach?”
These questions are compounded by the individual differences that make each learner unique. The teacher needs tested methodology to answer these questions effectively, and the time to apply it! Failing this, the teacher needs the results of research that looks at the likely range of answers to these questions in the topic area and level of class being taught. The present research is focussed on a particular topic area (chemical bonding) and a specific level (GCE A level), and is attempting to find out what general answers can be obtained from working closely with individual students. The present paper concerns one individual student I worked with during the pilot stage of my research, and treats the data obtained as a case study. I will be focussing on the questions of how readily basic learning develops into more sophisticated understanding, and how readily “misconceptions” may be displaced. Although the data from one student in one topic area is no basis for generalisation I believe the case study will be of interest to all teachers and researchers who are concerned with answering the key questions (above) in their own areas of work.
Introduction: Purposes of this paper.
There are two main purposes to the present paper - both implied to some extent in my title. I wish to discuss the extent to which a young person’s ideas in a particular science topic area change, or remain static, over a period of time, and interweaved with this I would like to explore the strengths - and limitations - of a case study approach in such an enquiry.
I intend to achieve these purposes through the following stages. First I wish to make explicit some of the assumptions that underpin my research and explain why I believe it is important that such work is carried out. Then I will outline the methodology being developed. Next I will introduce the topic area that forms the focus of my enquiry. With this foundation in place I will then discuss my interpretations of an individual student’s developing conceptual framework in this area of science.
Theoretical stance underpinning this research.
The following principles form part of the researcher’s own belief systems, and are implicit in the current research:
1. Meaningful student learning involves construction of knowledge in the mind of the learner, and is not a simple process of transmission from the book/teacher/instructor/lecturer.
2. Construction of meaning by the learner is a process that does not occur in isolation, but in the context of existing knowledge and beliefs.
3. Each individual learner is unique, and different learners’ conceptual frameworks will not be identical.
4. Conceptual change does not usually involve the sudden acquisition of complex new conceptual frameworks, and the complete abandonment or forgetting of previously existing knowledge, but tends to proceed over time, and usually in a step-wise manner.
5. It is in the interests of the teacher who wishes to promote effective learning to know her students, and (as far as possible) their existing frameworks of ideas.
6. The learner is not always explicitly aware of their own knowledge and beliefs, but is likely to hold tacit beliefs that may have significance for new learning.
7. The attainment of a particular concept or framework, as demonstrated by its application in a particular context, does not exclude the co-existence of other concepts or frameworks that may be inconsistent, and may be applied in another context, or even in the same context at another time.
None of these ideas are novel, and most are widely supported amongst researchers into learning in science. This stance places my own work within the rather catholic church of ‘constructivism’ (e.g. Pope & Watts, 1988; Watts & Bentley, 1987.) In addition the emphasis on the uniqueness and importance of individual learners leads to a research enquiry which leans towards what has been called ‘paradigm 2’ research (Gilbert & Pope, 1986, pp.22) - a more naturalistic form of enquiry (Guba, 1978) with an emphasis on qualitative data analysis. The present paper has no statistical content, but deals with the case study of a single learner.
Research has suggested that many teachers undertake their professional work as though they implicitly believe that teaching is about the transmission of ideas from the teacher’s mind to the pupil’s mind (Fox, 1983). Although there is much talk of teachers and lecturers being ‘facilitators’ this does not necessarily suggest a fundamentally different philosophy: rather that the source of the information passed into the student’s mind is some resource other than the teacher herself.
Any idea that learners have empty minds waiting to be filled with knowledge neatly packaged through education is untenable in view of our current understanding of human learning. It is important for teachers to understand this point, as a tacit belief in a ‘transmission’ model of teaching leads to a certain set of reasons that may be logically blamed for ‘learning failures’: the teacher did not explain properly, or the student was not paying attention, or there is some fault in the transmission line (the teacher could not be heard, or perhaps the student could not read the board.) Practising teachers will know of instances when they gave an excellent presentation, the class were quiet and attentive, a full set of clear notes were transmitted to exercise books; but later work suggested that the teacher’s knowledge and understanding were not transmitted to the class. It is important therefore for teachers to learn more about the way their students learn, so that they may plan and act accordingly.
The seminal work of Jean Piaget made clear - what parents have known down the ages - that there is an element of biological maturation involved in determining what children of different ages are capable of understanding and learning. Although the details of his stage theory have been much criticised, Piaget’s genetic epistemology (Miller, 1986, Chapter 7) has been of immense value. Work on cognitive acceleration based at Kings College London (Adey, 1992) has grown out of this field, and many researchers still draw inspiration from Piagetian ideas (e.g. Case, 1989; Castro & Fernández, 1987). Aside from his own theoretical construction of the way children’s style of thinking develops as they grow, Piaget established the use of the clinical interview as a key technique in such studies (Posner & Gertzog, 1982). The value of this methodology seems apparent to anyone who reads the interview data: transcripts that make it very clear that young children think very differently to adults about many aspects of the natural world. Perhaps just as important is the way in which much of this undulate thinking appears to be untutored: children spontaneously develop ideas about parts of their environment, and the relationships between such phenomena.
The work of George Kelly is also of importance in understanding how people learn, and why sometimes - in the view of their teachers at least - they don’t. Kelly saw people-as-scientists, a metaphor that suggests that people try to make sense of the environment by a constant process of forming conjectures and hypotheses that are open to testing and change (Pope, 1982; Pope & Watts, 1988; Watts & Pope, 1989). Kelly uses the idea of polar ‘constructs’ by which people evaluate phenomena, and although his work was primarily developed in the context of social relations rather than conceptual learning, it has lent itself to the evaluation of learners’ conceptual structures (Swift et al, 1983). The most important lesson of Kelly’s work for science education though is the principle that learning is an active process: and students actively try to make ‘sense’ of their environment, and impose (‘build’) structure upon it.
Although the work of Piaget warns teachers that they are unlikely to be able to teach certain concepts to young people until their thinking has reached certain levels of maturity (e.g. Shayer & Adey, 1981), Kelly’s legacy seems at first sight much more promising: people tend to actively make sense of what is attended to in their surroundings. So surely all the teacher has to do is make sure the learner’s attention is focussed in the right place. Unfortunately not!
For one thing it has been suggested that the human brain is a product of evolution such that it is predisposed to a certain kind of sense, and this ‘common sense’ is not the same as scientific sense (Wolpert, 1992.)
Science teachers meet their students after they have already spent some years actively making sense of the world, based on limited data, and using their ‘common sense’. By the time of formal teaching the young people already have a network of interrelating ideas about many of the natural phenomena that the science teacher wants them to learn about (Driver & Erickson, 1983; Gilbert & Watts, 1983; Driver, Guesne & Tiberghien, 1985; Osborne & Freyberg, 1985.) Or rather to re-learn about. And perhaps this will require a certain amount of unlearning.
This last point is one of the central interests of constructivist teachers and researchers. If learning involves making sense of the world, then the teacher should try to relate new ideas to existing ones. But if the existing ideas are not only wrong from the scientific viewpoint, but are inconsistent or even contradictory to the ideas the teacher wishes the student to learn, then how should teaching proceed?
One premise of the constructivist school is that it is important to find out what the learner knows, to make explicit the current ‘knowledge’. This provides the teacher with information about how to link new ideas to existing knowledge. It also makes any alternative conceptions explicit to the learners so that they may be challenged. Such challenges are unlikely to succeed based purely on the authority of the teacher, and it is common to suggest that counter examples are presented to ‘disprove’ the misconceptions, and that students are allowed to explore the logical consequences of their ideas, where these consequences may well be in conflict with new evidence or other beliefs they hold. The Children’s Learning in Science project (CLiSP) has published exemplar material illustrating such an approach (e.g. Wightman, Green & Scott, 1986; see also Scott, Dyson & Gater, 1987.)
There has been much research into the nature of student misconceptions / alternative conceptions / naïve theories / alternative frameworks / intuitive theories in science, although these have not been evenly distributed across the whole science curriculum. Some of this material is of the “before and after” school looking at how the ideas present in a group of learners differ following an intervention (i.e. teaching.) Much of the research is based on statistical analysis of paper-and-pencil tests {e.g. Andersson & Kärrqvist, 1983 (light); Bliss et al, 1988 (physics); Shipstone et al, 1988 (electricity); Sumfleth, 1988 (chemistry); and Viennot, 1979 (forces)}, rather than in-depth investigation of individuals, although the CLiSP team have used a much more imaginative approach: following up such statistical research with “naturalistic” case studies of classes experiencing current practice, and action research introducing constructivist teaching schemes (e.g in particle theory: Brook, Briggs & Driver, 1984; Wightman, Green & Scott, 1986; and Johnston & Driver, 1991 respectively). Also, as Black has pointed out (1989, pp.3-4.) there has been little attempt to undertake genuinely longitudinal studies following students over significant period of time. In practice little is known about the way students’ conceptual structures develop, and in particular how a students’ alternative framework may come to be replaced by the ‘orthodox’ scientific idea. How much of an impediment to new learning are misconceptions? Are the alternative ideas completely replaced and forgotten? Or does the (successful) student only acquire a second set of ideas, and the strategy of applying the new set in the context of science classes and tests? Do some leaners integrate new (scientific) and existing (alternative) ideas, even when they are logically inconsistent? Is the adoption of a new framework a simple case of applying logic and choosing the set of ideas which best explains the available data, and if so is the alternative framework discarded as soon as it is refuted (a Popperian model, if we make comparisons between individual learning and the progress of science); or does a revolution in thinking come as a gestalt-like paradigm-shift when the evidence is overwhelming and one’s emotional commitment to the previous framework will no longer suffice (a Kuhnian interpretation); or is maturation of a learner’s science knowledge like a progressive Lakatosian research programme (Watts & Pope, 1982); or does the learner subconsciously undertake a complex comparison, selecting the framework with greatest explanatory coherence (Thagard, 1992)? Only detailed examination of individual student ideas, over an extended period of time, is likely to suggest the most appropriate model, which could then inform teachers, curriculum developers and perhaps learners themselves.
Methodology.
I am in the process of developing methodology to explore the development of A level students’ understanding of chemical bonding. The work being reported today forms part of pilot study, and uses one research technique - a clinical interview where the student talks to a single researcher (myself) with a series of prepared diagrams as foci for the discussion. The interviews are recorded onto audio tape.In my ongoing work I am supplementing this technique with other means of collecting data, but in the present case study the data presented were obtained from a series of four interviews.
The interviews took place at three stages during the student’s study of A level chemistry. The first interview was undertaken at the start of the second term of the course (before the topic of concern had been explicitly studied.) The second interview took place at the end of the first year, and the third interview was conducted a few weeks before the final examination. This latter interview did not allow discussion of as much material as had been hoped, and it revealed that the student had serious misconceptions about some of the fundamental chemical ideas being considered. A short ‘tutorial’ was undertaken at the end of this interview, and the a follow-up interview took place two weeks later. As the interviews took place over an extended period of time (from January 1991 to May 1992) they provided data giving insights into changes in the students’ understanding of chemical bonding.
It has been suggested that educational enquiry can be related to a continuum of research styles that at one end (exemplified as so called paradigm 1) follows conventional scientific method, using control of variables and statistical inference. Such an approach could be typified by teaching two equivalent classes the same topic, but one subject to an intervention treatment, and the other being a control - taught in exactly the same way in terms of all relevant variables except that being studied. Statistical comparison of pre- and post- test scores in both groups leads to inferences about the effectiveness of the intervention. The procedural difficulties of controlling all relevant variables make such an approach exceedingly difficult. Research at the other end of the continuum, so-called paradigm 2 enquiry, takes a more naturalistic approach. Rather than plan an intervention, one tries to learn as much as possible by an in-depth examination of the behaviour of the individual or group being studied. To some extent this “anthropological” approach is more suited to social research than cognitive studies - if only because some form of ‘intervention’ is likely to be needed to provoke our subjects into thinking about an abstract topic like chemical bonding.
So my own research occupies an intermediate position on the research continuum. My main method of data collection involves clinical interviews, in a quiet room away from the normal class context, with a tape recorder running. As I have a dual relationship to the student subjects, both researcher and teacher, I have a responsibility to intervene at some stage when they have misconceptions, rather than just observe and note their thinking. (This does not necessarily have to be done ‘on tape’.) However, I would view my basic stance as a researcher as naturalistic : I wish to explore the students’ ideas in depth, and ‘get inside their heads’. I am therefore trying to work with a limited sample of students, over an extended period of time, rather than using large scale survey techniques. One important aspect of my stance is that the people I am working with are known to me as human beings, and are not just experimental subjects. My research could be construed as action-research as I ultimately hope to learn how to teach ‘better’, and that is a concern that effects my students. It has been suggested that in action research the people with whom the teacher-researcher works in the enquiry should be called co-researchers. I do not think this term is meant to imply that the co-researchers are actively undertaking their own research, rather that they share an interest in the research, but nevertheless it seems a misleading term. I would prefer to call the students that I have been working with co-learners. We get together so that we can learn: they primarily wish to learn more about science, and I wish to learn more about their understanding of science, and we both consider that time spent discussing chemistry will be beneficial in meeting these goals. In Black’s terms my interviews may be “seen as a piece of learning and as a conversation between researcher and pupil” (1989, p.3.)