Teaching Chemistry in Primary Science: What Does the Research Suggest?
Skamp, Keith, Teaching Science
The new Australian national science curriculum includes chemistry content at the primary level. Chemistry for young students is learning about changes in material stuff (matter) and, by implication, of what stuff is made. Pedagogy in this area needs to be guided by research if stepping stones to later learning of chemical ideas are to facilitate conceptual progress rather than hinder it. Further, recent findings advocate both the informal and formal introduction of aspects of the particulate model of matter at the primary level, provided certain teaching and learning strategies are used.
CHEMISTRY IN THE NATIONAL PRIMARY SCIENCE CURRICULUM
The Australian Curriculum: Science (ACARA, 2011) outlines the 'science understandings' that primary (F-6) students are to encounter in the chemical sciences. In Foundation (F) to Year 2, the focus is awareness of self and the local world, while in Years 3-6 it is on what can be investigated scientifically. Chemical content descriptions and exemplar 'elaboration' examples for F-6 are in Figure 1 and are compared with a suggested progression based on recent research. Further examples of F-6 chemical activities linked to these ACARA understandings, are in ASTA's National Science Week resource book (Bucat et al. 2011).
As 2011 was the International Year of Chemistry, it is appropriate to ask how can primary teachers assist students in their conceptual understanding of these chemical ideas. The curriculum refers to 'objects', 'materials' and 'substances', as well as 'solids', 'liquids' and 'gases', and 'reversible' and 'irreversible change'. What do primary students intuitively think about these concepts and processes? How does their thinking develop? In what ways can teachers effectively assist concept formation related to these chemical ideas? Irrespective of the intentions a teacher may have when they engage young learners in activities connected with these concepts and understandings, their learners will inevitably ask questions and make comments such as 'what has happened and why?', 'where has it gone?', 'what is it now?', 'I think that it is ...' and so on. What are teachers to say and do in such situations?
In the following, the most recent teaching and learning research connected to primary students learning chemical ideas is overviewed. Suggestions for more effective pedagogy are identified. Further, with an increasing focus on students learning through generating and testing their own representations of phenomena, more research is now indicating that this pedagogical approach can assist primary students in the stepwise development of a particulate understanding of matter. This is important, as the evidence points to certain teaching strategies enhancing later learning about this major conceptual scheme underpinning chemistry.
OBJECTS, MATERIALS AND SUBSTANCES
Each of these concepts is in the curriculum. Children are asked to think about what makes up materials such as plastics and glass. Initially it would be helpful if teachers were aware of their students' existing conceptions about these ideas: see Figure 2; differences also will be discerned in the following discussion. Young learners can usually distinguish between objects and the materials from which they are made, and with guidance, usually the properties and uses of each. Some materials, such as metals, are more readily understood than others. Many students appreciate that properties of materials could be determined through scientific investigation, which is a curriculum focus for Years 3-6. Students though, usually have difficulty appreciating the origins of different materials (Krnel, Watson & Glazar, 1998; Russell, Longden, & McGuigan, 1991). There are exceptions to these generalisations such as students not realising that some materials and substances, which can occur in a range of forms, are not the same; an example would be iron powder and pieces of iron (Wiser & Smith, 2008). …