“We use practical work in science classes when students are unlikely to have observed the phenomenon we are interested in – or to have observed it in sufficient detail – in their everyday lives. In such situations, it is essential and irreplaceable.” (Millar, 2004, p. 9).
“The centrality of the laboratory to the teaching of science has become like the addicts’ relationship to their drug; an unquestioned dependency which needs to be re-examined and weakened if not broken altogether.” (Osborne, 1998, p. 156).
The juxtaposing statements above form the base of this research piece on the place of practical investigation in our curriculum. Both authors are well respected in their fields, and both have completely opposite views on not only the effective teaching of, but also indeed the very place of practical work in the Primary National Curriculum. This is particularly relevant as the curriculum is currently in a state of flux due to the National Curriculum Review.
The National Curriculum Review has stated that Science will be kept as a Core subject when the new curriculum is released next year, but until early 2012 it is not known exactly what the programme of study will entail. What is known is that teachers are being given the freedom to teach their subjects in their own way; they are being told what to teach, but not how to teach it, which is a massive step forward from the old curriculum (National Curriculum Review, 2011). However, this does raise concerns about how, and indeed if, teachers should incorporate practical work and experiments into their lessons, or if it is easier to teach scientific concepts through other means, such as videos and worksheets.
This research piece will draw on both literature reviews and the author’s own personal experiences and observations in an effort to ascertain whether or not practical investigation is indeed an effective method of teaching science, or whether the risk of it being taught poorly negates its place in the curriculum entirely.
So what is practical work? In recent decades the role of practical work was – and to some extent still is – heavily influenced by the Nuffield science teaching projects of the 1960s. These projects aimed to turn pupils into scientists in their science lessons, and so many new experiments and apparatus were integrated into school science. It was assumed that if children were allowed to make the necessary observations of selected experiments and procedures then they would be able to infer and conclude scientific laws and theories by themselves too.
Nowadays, it is clear that children will not arrive at the laws of science by a process of natural intuition, and nor is this the way that real scientists arrive at these conclusions either (Alsop & Hicks, 2001).
With this in mind, the role of practical work is becoming more creative and teachers are using methods other than just laboratory-based work to get children involved. Practical work now includes: group discussion, science trips, videos and interactive whiteboard resources, ICT programmes and whole class/pair/group and individual experiments. Due to these recent changes in understanding how children learn, practical work in science is evolving and there is a lot of support for it, whilst still some arguments against it.
Wellington (1998) states that there are at least six types of activity that take place in school science that we would probably all class as practical work: teacher demonstrations, whole-class practicals (with all learners on similar tasks), working in small groups, a carousel of experiments with small groups engaged in different activities (rotating round each experiment) and investigations organised in one of the above two ways. In order for teachers to feel confident about teaching each one, it is obvious that they need to practise and gain experience of each technique.
Wellington (1998) also presents three arguments and corresponding counter arguments for doing practical work: the cognitive argument, the affective argument and the skills argument. The cognitive argument is based on the premise that by carrying out practical work, children will better understand complex theories and abstract concepts of science education as these can be visualised and confirmed by their own experiences. However, in 2000 Wellington admitted that practical work can lead just as easily to confusion as to clarity of understanding, especially if the teacher is not entirely comfortable with their subject knowledge.
The affective argument is the belief that practical work helps to generate interest and motivation for the subject. Wellington believes that pupils’ find it easier to remember the information and that the excitement around the subject means they will concentrate better. However, Johnstone & Wham (1982) noted that whilst pupils do indeed enjoy practical work and pick up motor skills with varying degrees of proficiency, they actually learn little of the theoretical information that practical work is purported to initiate and provide.
The skills argument claims that practical work helps to promote the development of intrinsically valuable skills such as: observation, inferring, investigating and hypothesising. However, Hofstein & Mamlok-Naaman (2007); and Jenkins (1999) also argue that the practical skills children learn in laboratory-based science lessons bear no relation to the real world of scientists, where many of the techniques that children learn are now either outdated or completed by automated machines. They believe that the problems children encounter in the classroom are psuedo scientific, with children often knowing the answer and the outcome before they begin, meaning that the work becomes “a lengthy elaboration of the obvious” (Leach & Paulsen, 1999, p.27).
It is not only Wellington who believes that practical work in science should play a role in our curriculum; both the government and researchers such as Dillon and Woodley also argue that practical investigation in science is one of the most effective methods of successfully teaching difficult scientific concepts to children, as it allows children to gain a wide range of skills. These include: giving the child first-hand experience of scientific equipment, materials, living things and artefacts, increasing the child’s sense of ownership, improving the child’s social skills, teaching them how to work safely and responsibly and teaching them observational, analytical, critical and evaluation skills, as well as motor skills (HMI, 1999; Dillon, 2008; and Hodson, 1993).
Aside from the government and researchers’ believing that practical investigations are an important aspect of science; teachers and students are positive about practical work too. For example, in a recent NESTA survey (n=510), 99% of the sample of UK science teachers believed that practical and enquiry-based learning had a positive impact (83% – ‘very’; 16% – ‘a little’) on student performance, understanding and attainment (NESTA, 2005a, p. 5).
Whilst it is true that the quality of practical work varies considerably, there is strong evidence – both from this country and abroad – that, “When well-planned and effectively implemented, science education, laboratory and simulation experiences situate students’ learning in varying levels of inquiry, requiring students to be both mentally and physically engaged in ways that are not possible in other science education experiences” (Lunetta et al., 2007, p. 405). Evidence of effective practice in the use of practical work comes from a range of studies. For example, White and Gunstone’s (1992) study indicates that students must manipulate ideas as well as materials in the school laboratory, as this helps to deepen their understanding by allowing them to gain experience of scientific concepts and activities for themselves, which creates a physical (“hands-on”) to cognitive (“brains-on”) link.
There is a growing body of research showing the effectiveness of linking hands-on and brains-on activities in school science both inside and outside the laboratory. Brains-on refers to scientific ideas that account for children’s observations, and hands-on occurs when children build a bridge between what they can see and what they are handling. Making these connections is challenging, so practical activities that make these links explicit are more likely to be successful (Millar, 2004; Lazarowitz & Tamir, 1994; and Hofstein & Lunetta, 2004).
With so much research in favour of practical work, it is perhaps surprising to learn that some bodies still dispute its worth and effectiveness. However, this is largely due to concerns over teachers’ subject knowledge and planning skills. Research shows that teachers are not confident when it comes to teaching science practically, and also that they do not always have a clearly defined beginning, middle and end to their lessons, which is paramount to children’s understanding. Many teachers are also far too vague with their learning objectives and success criteria. Abrahams & Millar (2008); Wellington (1998); Woolnough and Allsop (1985); and Gough (1998) found that many ‘experiments’ are nothing of the sort, and that teachers need to devote more lesson time to helping students discuss ideas associated with the phenomena they have produced, rather than seeing the successful production of the phenomenon as the most important – and sometimes only – learning objective.
Whilst the National Curriculum (Great Britain. Department for Education and Employment, 1999) specifies that practical and investigative activities must be carried out by pupils, and (as previously discussed) there is research to indicate that generally teachers strongly advocate the use of practical work and experience, it has to be noted that there is still a gap between policy and practice; between what is written in curriculum documents, what teachers say they do and what pupils actually experience. For example, Lunetta et al. (2007); Hodson (1993 and 2001); and Wilkenson & Ward (1997) note that despite a recent shift of emphasis towards learning outcomes and success criteria, there is a ‘chasm’ between what teachers identify as their outcomes before lessons and the outcomes that their students perceive after the lesson has finished. Hodson (2001) found that teachers’ stated lesson aims frequently failed to be addressed during actual lessons and that often children left lessons unaware of what the learning outcome was, and whether or not they had achieved it.
Tamir and Lunetta (1981) found that despite curriculum reform aimed at improving the quality of practical work, students spent too much time following ‘recipes’ and, consequently practising lower level skills. As a result, students ‘failed to perceive the conceptual and procedural understandings that were the teachers’ intended goals for the laboratory activities’ (Lunetta et al., 2007, p. 403). This pattern of under-utilisation of the opportunities provided by practical activities has been reported by several researchers including: Tasker, (1981); Hofstein and Lunetta, (1982); Champagne et al., (1985); Domin, (1988); Eylon and Linn, (1988); and of course not forgetting Osborne (1998)!
With so much debate over practical science, it is hardly surprising that many teachers lack the confidence needed to teach it successfully. Teachers’ subject knowledge needs to be completely sound, and they also need to be aware that things may happen in the experiments that they are not anticipating; the outcome may not always be what they expect; but there is always something valuable to be learnt from practical science, at least in this author’s opinion. The author observed many instances where practical science was being taught effectively, and some where it was not so useful for the children and these are detailed in the case studies below.
The first case study the author observed was in a Year 3 class, where the children were learning about light and shadow using shadow puppets. This was a particularly effective use of practical science as it was also cross-curricular. The children used techniques they had learnt in both Art and Design and Technology to create their own shadow puppets after the teacher had modelled it to them. They also gathered ideas from watching a video where a puppeteer explained that different materials could be utilised to make the puppets, and she put on a short show herself. The children experimented with different opaque materials such as card and wood, as well as translucent and transparent objects such as paper and transparent film, which they coloured in. The teacher allowed the children to experiment freely; only giving them very basic guidance on the best materials to use and how the light should be positioned in an attempt to let the children discover the best materials and position themselves. Feedback from the children was highly positive, with many saying the activity had been lots of fun and that they now knew that opaque materials were the best to use, and that to make things seem bigger the light needed to be further away, or closer for making things appear smaller. The teacher had succeeded in her learning objective of helping the children understand that shadows form when light from a source is blocked in some way, by either translucent or opaque objects, and she was more confident in teaching practical science after that, so the author believes this was a positive instance of practical science being used successfully.