Class six children are sitting in a large semi-circle. Victoria gets up to stand by a piece of paper lying on the floor near the front of the arc. She picks up some red plastic interlocking cubes and puts them in a plastic box she is holding. Then she walks around the arc, stopping every so often to put a cube on one of several paper labels on the floor, returning eventually to where she started.
But this is no drama workshop or construction game. It is class six's first lesson in a series on the heart and human circulation, and Victoria's teacher has chosen this activity to show how the system works.
The labels on the floor bear words such as "liver", "kidneys" and "muscles". As the children take turns to walk around the "system" their teacher explains what their actions represent - showing how the body's organs are supplied with the oxygen they need.
The lesson is part of the Introducing Scientific Concepts to Children research project, sponsored by the National Foundation for Educational Research. The project investigated the natural, intuitive approaches key stage 2 teachers use to introduce scientific ideas in the classroom.
Much has been made over the past 10 years of the difficulty in putting over scientific concepts, and various strategies have been developed to tackle the problem of children's persistent misconceptions. But, with a few exceptions, these have been aimed at secondary school science specialists. How should non-specialist primary school teachers, with limited training in science education, proceed?
The project started by assuming the best way to to address the question was to identify where teachers were, and look at ways of refining and building on existing practice.
Ten teachers took part in the research, which concentrated on two areas of scientific understanding - the human circulatory system and the Earth's movement in relation to the Sun. Introductory lessons in each topic were videotaped. Following the lesson, some of the children were interviewed to find out what they understood about the topic and how that understanding related to what had gone on in the lesson. Each teacher completed a logbook, giving further details of the schemes of work.
The teachers used a wide variety of approaches. As well the drama-based activities of Victoria's class, they made models, carried out various investigations and used computer simulations, diagrams and photo-graphs. Our analysis of the lessons showed the wide variety of approaches contained some common threads.
First, the central pillar of each lesson was teacher talk. Lessons were firmly directed by the teachers, and each step had been planned. This level of direction was maintained through all elements of the lessons, including practical work. Investigations were set up to put across particular ideas, rather than, for example, as tests of children's own theories. The questions being investigated were essentially the teachers' questions.
While the teachers' repertoire may have included somemore open-ended approaches, they were not evident in these lessons, emphasising the priority given to imparting new knowledge.
Previous research has shown the difficulty of getting children to accept "school science", much of which may seem counter-intuitive to them, and has underlined the importance of children's preconceptions in the interpretation of scientific ideas. This project suggested teachers ignored children's existing understanding. In fact, the position was more complex.
Previous research aimed to identify typical misconceptions and devise teaching sequences and approaches to confront them. Our teachers took a different tack. Almost all used some form of analogy to link familiar, observable objects and events to unfamiliar and unobservable ones. They were creating a "picture" of the scientific content.
Victoria's lesson on the circulatory system showed this process in action. The familiar plastic cubes were used to represent something else - "These are oxygen, not multilink," the teacher pointed out.
The paper labels were organs in the body, and the children's actions showed how blood and oxygen move around the system as they are pumped by the heart. And the representation seems to have worked, judging by the children's responses to the interview questions.
Building pictures of unfamiliar territory using more familiar material seemed to come naturally to the teachers. It is, potentially, a powerful way of using experience to understand new ideas, and one that has an affinity with the way in which scientists create idealised models of the way they believe the world is structured.
How can teachers make the best use of this method? One area teachers need to consider is making appropriate links between the features of the analogies they use and the world these represent. No analogy matches what it represents in every respect, and it can be important to point out where this is the case.
It would also help if the children were aware of why analogies are useful - not just as a teaching aid, but as a new view of the world that helps us understand how it works - a way to liberate our thinking.
This implies a subtle shift in teaching, from "this is the way things are" to "this is a good way of thinking about how things are".
Observations of the lessons suggest that (from the children's point of view) they often lacked an explicit rationale for why the activities in the lesson were as they were, and how they were related. What was the link, for example, between the piece of drama described above and the investigation that followed it, in which children measured their pulse rates before and after exercise to answer a question posed by the teacher?
Children tended to treat these as separate events. By making more central the notion that science provides models of reality with great explanatory power, we may introduce scientific concepts in a way that is not only effective in helping children acquire these ideas, but also better reflects the nature of science itself.
Dr Steve Sizmur is a senior research officer at NFER and leader of the Introducing Scientific Concepts to Children research project. John Ashby is also a senior research officer at NFER. Their book Introducing Scientific Concepts to Children explores these themes further. It is available from NFER Publications, The Mere, Upton Park, Slough SL1 2DQ