2.3 Practical work and science content knowledge
Learning science content knowledge through practical work typically involves students completing tasks that have an outcome known by the teacher, such as measuring the loss of heat from cans insulated with different materials. When students do not obtain the expected results, they are often told that something must have gone wrong, or their results are explained away. What do they learn about science and themselves as a scientist from such experiences? Perhaps they learn that science is about getting the ‘right’ answers, or that they are not good at science.
However, such routine teacher-led practical work has the potential to support learning. Previous approaches include the ‘discovery’ method. In Chemistry: Handbook for Teachers for the original Nufﬁeld Chemistry O-level course (The Nuffield Foundation, 1967, p.63), the following advice appears after a description of some of the practical work that pupils might undertake:
given sound preparation and skilful guidance the class will discover or invent the main postulates of Dalton’s atomic theory.
There does not seem to be any recognition here that this theory is an enormous leap of the imagination, not simply a generalisation of observations from practical work. Not only would it be unrealistically optimistic to expect pupils to construct these kinds of scientiﬁc theories for themselves, but it would also be a serious misrepresentation of the nature of science.
The teacher-constructed type of practical so often used also does not reflect the nature of science. But does this matter? Millar (2002) argued that practical work designed to support learning of content knowledge is about communicating what is already known and does not have to be an authentic science experience. Such experiences provide students with the opportunity to talk, write and think about phenomena ‘from within the “mental landscape” and using the terminology of an imagined model’ (Millar, 2002, p. 55). Through this it has the potential to build a bridge between objects and observable properties, and the realm of idea (Millar, 2002, p. 58).
The typical teacher-led practical work activities have an important role in school science education. However, done without thought and focus, practical work may not develop students’ conceptual understanding; used unthinkingly, it may only entertain pupils and simply waste learning time. It is therefore imperative that science teachers understand the different types of practical work available and match tasks to specific learning outcomes. The Association of Science Education’s (ASE) Getting Practical programme of professional development for teachers of science at the primary/elementary and secondary phases of education aims to improve the effectiveness of learning through practical science lessons. The website provides useful links and resources to support effective practical work in science.
Activity 7 Getting practical
Spend some time exploring thewebsite.
Read the Getting Practical framework (SCORE, 2011), which provides an outline for thinking about practical work in science, including what it can be used for, the different purposes of practical work and a checklist for best practice.
Use the framework to analyse and evaluate the practical work you have used in two or three lessons taught or observed recently. In particular, you should identify:
- the nature and purpose of the practical work
- how it supported students’ achievement of the learning objectives.
Use the ‘best practice’ checklist to evaluate the use of the practical work and identify how it could be used more effectively.