This is an account of a study on the nature of children's scientific understanding of the concepts of floating and sinking, and the role of cognitive challenge and scaffolding in supporting conceptual change. The procedure involved the analysis of video-recorded interviews conducted with two female participants of different age.Results showed that, while the younger participant's reasoning was confined to her concrete experience, the older participant developed a more sophisticated understanding of scientific concepts, which is consistent with Piaget's argument that scientific reasoning requires the development of specific cognitive structures.
Moreover, the older participant demonstrated conceptual change when faced with conflicting evidence, and her progresses were supported by scaffolded discussion. On the other hand, the cognitive challenge did not spurred a real qualitative cognitive change in the younger participant. Moreover, she seemed to benefit less from adult guidance and displayed a less clear progress in her reasoning, in contrast with Vygotsky and Wood's predictions.Introduction.
The ability to think about the world in terms of symbolic representations is an essential pre-requisite for understanding mathematical and scientific principles. According to Inhelder and Piaget (1958), it is only in the latter stage of cognitive development, known as formal operation stage, that children develop abstract thinking and their understanding of the world becomes less constrained by their concrete experience of the world. Scientific reasoning is linked to development of related cognitive structures and, as argued by Piaget, conceptual change is triggered by the conflict between children's current thinking and the actual evidence, which forces them to adjust their reasoning in the course of a process known as equilibration. A teaching approach known as discovery learning places major emphasis on the role of the teacher in challenging and stimulating children's reasoning with contrasting evidence.
Selley (1993) supported the idea that children's understanding of scientific concepts develops through stages, and argued that teachers should encourage children in formulating their own explanations and hypothesis in the light of the evidence available to them, suggesting correlations and stimulating their reasoning. While implausible explanations should be challenged, he states, teachers should not force them to accept hypothesis that are too demanding or difficult to grasp for their current cognitive abilities: as their experience of the world widens with age, children will be more prone “to adopt a new explanatory model” (Selley, 1993). Alongside teachers' support, conceptual change is aided by cognitive conflict in peer interaction, as shown by studies conducted by Perret-Clermont (1980) and Doise and Mugny (1984). Howe et al. (1991, 1992) also demonstrated that resolution of interpersonal conflicts during group work results in a greater individual progress in terms of understanding scientific concepts.Focusing on the social nature of cognitive development rather than its necessary cognitive structures, Vygotsky (1978) argued that social interaction was functional to the creation of a zone of proximal development; that is, the difference between a child's individual cognitive progress and that achieved by working with others.
In this context, adults and more able peers can aid cognitive development through what Wood (1988) termed as “scaffolding”.The aim of the present study was to explore the nature of children's scientific reasoning with a specific focus on the understanding of the concepts of floating and sinking, and the role of cognitive challenge and scaffolded discussion in supporting conceptual change. The investigation was carried out by analysing and coding children's responses during two semi-structured interviews.Method.Design.The present study involves a comparative analysis of the responses given by two participants during semi-structured interviews and practical tasks.
Participants.Two participants, Emily (female, aged 6 years 7 months) and Jessica (female, aged 11 years 10 months), were selected for this study from a larger sample of children within the age range 6–12 years from a primary school in the Milton Keynes area who had agreed to take part in this study.Material.The material included two video-recorded semi-structured interviews provided by The Open University (The Open University, 2013) and dated July 2012. Technical apparatus included cameras, lights, and a microphone boom.
For the practical task, a large plastic tank of water and 18 objects were used, classified according to the following categories: light floaters, heavy floaters, light sinkers, heavy sinkers. Detailed object list can be found in Appendix 1. Scales were used to compare weights in the latter part of the interview.Procedure.The interviews were conducted by Natalia Kucirkova, a doctoral student from The Open University, with the technical support of the film director, two camera operators, a sound recordist and an assistant. The interviewer had no previous knowledge of the participants.
To protect the children's anonymity, only their first names and age were provided. Informed consent of parents for their children's participation to the interviews was obtained. The participants were informed of their right to withdraw at any moment from the study, in conformity to the BPS ethical guidelines. For both interviews, the technical setting, including the presence of the technical staff, was arranged so to be as unobtrusive as possible, and potential elements that could have inhibit the participants were considered (the interviews took part in a familiar settings).
The investigation involved a semi-structured interview and a practical task, and features three parts. Each part included three stages. The details of the interview protocol, provided by The Open University (2013), have been included in Appendix 2. Part A assess the participant’s initial understanding with light objects that float and heavy objects that sink. Part B assess the participant’s initial understanding with light objects that sink and heavy objects that float. In both parts, the experimenter presented the children with a set of objects and asked them whether they thought the object would sink or float and why.
The children were then asked to test their prediction by placing each object in the tank of water, and to explain why the objects were floating or sinking. Part C focuses on developing children's understanding.Both interviews were transcribed and the children's answers were coded. The number of answers for each category was counted.Results.
Appendix 1 includes detailed data sheets for both participants that show both predictions and explanations for each object presented. The percentage of accuracy for Emily's prediction was 22.2% compared to 52.7% for Jessica's predictions. Most of the wrong answers concerned unfamiliar objects (the small wood block, the spanner) or objects whose weight was considered as more important in making a prediction than other characteristics (as for the tin lid, the white candle, the yoghurt pot, the needle and the coin)Table 1 shows the number of explanations for each causal theme at stage 2 and stage 6-7 of the interviews, and the total number of explanations given by each participant.
