Does Practical Work Really Work?

Critical review: Abrahams, I. and Millar, R., 2008. & Does Practical Work Really Work? A study of the effectiveness of practical work as a teaching and learning method in school science, International Journal of Science Education, 30:14,1945 1969.

Practical work is regarded by many as key to learning in science education. The House of Commons Science and Technology Committee (2002) calls it a vital part of science education. However, studies by Hodson (1991), Osborne (1993) and Wellington (1998) (cited in Abrahams and Millar, 2008) question the effectiveness of practical work as a teaching and learning tool.

Prior studies of school science practical work (Beatty Woolnough, 1984 & Thompson, 1975 cited in Abrahams and Millar, 2008) focussed on views of teachers and students regarding practical work, views which the authors believe to be rhetorical rather than realistic. (Abrahams Millar, 2008). By observing lessons, the authors aim to study practical work as it is carried out in schools.

The authors observed 25 different KS3-4 practical lessons at eight different schools broadly representative of secondary schools in England. The lessons covered the five years in KS3 4 and included biology, chemistry and physics topics. Observations were augmented with interviews with teachers before and after the lesson in order to record teachers objectives and reflection on the work undertaken. Where possible, groups of students were also interviewed, during and after lessons to draw further insights into their thinking. By combining interviews with observations of lessons, the authors intended to ensure that statements given in interviews were based on the reality of the practical work as conducted, rather than rhetorical beliefs about practical work in general (Abrahams Millar, 2008)

Data sources take the form of field notes taken in each lesson observed and tape recordings of interviews. The authors use a two-level model developed by Millar et al (Millar et al, 1999, cited in Abrahams Millar, 2008) to evaluate the effectiveness of the practical tasks. This essentially asks two questions:

1) Do the students do what the teacher intended?

2) Do the students learn what the teacher intended?

The authors reference Tiberghien's (2000) model of practical work as helping students make links between tangible objects and observables and the scientific ideas and concepts behind them. The authors construct and apply a two-level framework drawing on these ideas to gauge the effectiveness a particular practical task (table 1 appendix 1.).

Practical work as observed in the study is generally effective at getting students to correctly manipulate objects to produce observable phenomena but generally ineffective at getting students to use scientific concepts and ideas to explain the phenomena.

The paper attributes this to the importance placed on observables in the design and implementation of practical work and hence a lack of scaffolding implemented to enable students to make such connections. This in turn seems to stem from the assumption that the link between the scientific idea and the pattern of results, or in some cases the idea itself, will occur intuitively to students provided that they can correctly produce the phenomena.

The authors agree that a practical lesson is unlikely to teach the intended ideas if the student does not produce the expected phenomenon, but stress that if this is the sole focus of practical lessons, the lesson is unlikely to help students to learn scientific concepts something that was a stated objective of most teachers in the study. The conclusion is that improved scaffolding would produce practical lessons which are far more effective in allowing students to explain their observations in terms of accepted scientific ideas.

The paper finds that practical work is used by teachers almost exclusively to teach substantive scientific fact at the expense of teaching about scientific procedure. Again, a belief that by simply doing practical work, an understanding of scientific procedure and practices will be built intuitively seems to be behind this.

If this is typical in schools, it seems an opportunity missed. One of the most important things I remember from my own school science lessons was Mr Barlow, my teacher throughout KS4 5, repeatedly saying that obtaining perfect results was not the goal of practical lessons and that we could get an A for incorrect results, provided we could reasonably account for the discrepancy in our results (errors, uncertainty etc).

The excerpts from interviews and observation notes included in the paper seem to support the authors conclusions. Included are brief excepts from typical, ineffective lessons and lengthy excerpts from or relating to an apparently atypical, more effective lesson where greater time spent discussing scientific ideas seemed to lead to a better understanding among the students.

This seems a broadly reasonable assumption: The workings of a scientific phenomena are often invisible or even abstract and cannot be learned inductively from practical work (Leach and Scott, 1995 quoted in Wellington, 1998, also Wellington, 1998). In my own experience of teaching, I have found that unless carefully guided, most pupils do struggle to think about practical tasks in terms of scientific principles. For example, from a year 8 class of 30 pupils, none could answer the question why are we doing this experiment [burning magnesium in the presence of oxygen to create magnesium oxide]? despite the lesson starting with a discussion on the differences between the properties of compounds and those of their constituent elements. The link between ideas and observables, it seems, needs to be made very explicit for most students to use those ideas to think about the phenomena they encounter during practical work.

Without access to the authors notes, the reader has no choice but to trust that excerpts used by the authors to support their conclusions are indeed typical. Researchers own priorities can affect what they consider noteworthy in their observations (Weinberg, 2002). Augmenting observations with interviews can strengthen the evidence base (Denzim, 1970 also Robson 2002 cited Cohen, Manion Morrison, 2007). However, the interviewer will inevitably have some affect on the interviewee (Briggs, 1986 and Gicanel, 1974 cited in Holstein and Gubrium, 2002). Given that at least one of the two authors has previously published work criticising the implementation of practical work (Millar, 2002), there may be some unintentional bias.

Although only one teacher spent significant time discussing scientific ideas with the whole class, the authors quote another teacher discussing scientific ideas with small groups. It seems likely that other teachers would offer similar scaffolding during practical lessons indeed most teachers I have observed teaching practical lessons do so. It also seems likely that observers would struggle to record all such events, especially given that they did not video the lessons. Issues of regional bias could also affect the results of the study, given the sample size (Cohen, Manion Morrison, 2007).

The limited extent of and weaker evidence base for the conclusions about (medium-long term) learning (p. 1961) do not invalidate their findings, but do highlight a less obvious, but more fundamental problem with this type of study. Effectively, the study equates pupils can discuss the science of a practical task during or immediately after the lesson with the practical was effective . Lessons in school do not exist in isolation, but as part of a sequence. Students rarely assimilate scientific concepts instantaneously (Driver et al., 1985) and practical lessons can play a valuable role in a sequence of learning experiences designed to help students develop a scientific understanding of a given phenomenon.

Practical tasks can have purposes other than the teaching of substantive scientific facts: As illustration of phenomena predicted by theory or as an exercise to develop one or more skills essential to scientific practise (Wellington, 1998). Practical work can help students to build a lexicon of experiences to give meaning to concepts such as force , expansion , vigorous reaction , less vigorous etc. (Millar, 2002) Perhaps one of the most important aspects of practical work is the affective (Parkinson, 2002). Even critics of the practical science in schools such as Millar (2002) and Wellington (1998) note its capacity to inspire and enthuse. In the paper itself, the authors note that many of the practical tasks recalled by students were spectacular demonstrations such as the Thermite reaction. Such demonstrations are designed not to teach the students a specific set of scientific facts, but to capture the imagination and perhaps instil the idea that there are exciting things in science which they might more fully understand if they continue to study.

Most teachers in the study had, however, intended for their students to gain substantive scientific knowledge from the practical lesson and in nearly all cases, this was not achieved. If practical work is to be used to teach students substantive scientific knowledge, an appropriate degree of scaffolding must be planned. During my own school education, I remember several teachers insisting that the class agree on a hypothesis before allowing a practical task to proceed, something that focussed our thinking about our results/observations as either fitting or contradicting a trend predicted by theory. However, there are different types of practical task with different aims (Gott and Duggan, 1995). Woolnough and Allsop (1985) break them down into exercises, experiences and investigations.

The authors assert that using their own model of analysis would help teachers determine the degree of challenge in practical lessons and hence the level of scaffolding needed to ensure that most students learn what is intended. I would further offer that thinking about the type of practical task would enable teachers to plan and implement an appropriate practical task to achieve the learning objectives for the lesson and also the best way to support students in achieving those objectives (Frost, 2005), (Parkinson, 2002).

This paper has been useful to me: When I first applied for teacher training, my idea of a great science teacher was of someone using practical work as much as possible to bring scientific concepts to life, exciting and inspiring pupils as they learn. While I still think practical work can do all these things, I will be more aware of the difficulties students encounter in relating observations to science ideas and think about the ways I can appropriately scaffold different types of practical task.

(1647 words.)

Reference List:

Abrahams, I. and Millar, R., 2008. & Does Practical Work Really Work? A study of the effectiveness of practical work as a teaching and learning method in school science, International Journal of Science Education, 30:14,1945 1969.

Cohen, L., Manion, L., Morrison, K., 2000. lt;i>Research methods in education. London: Routledge.

Driver, R., Guesne, E., Tiberghein, A., 1985. & Some Features of Children s Ideas and their Implications for Teaching. & In: & Driver, R., Guesne, E., Tiberghein, A. eds. 1985. & Children s Ideas in Science. & Milton Keynes: & Open University Press.

Frost, J., 2005. & Planning for Practical Work. & In: Frost, J. Turner, T. eds. & 2005. & Learning to Teach Science in the Secondary School. & 2^nd ed. & Oxon: & RoutledgeFalmer. & Ch 5.5.

Gott, R. Duggan, S. (1995). Investigative work in the science curriculum. Buckingham, UK: Open University Press.

Holstein Gubrium, 2002. & Active Interviewing. & In: Weinberg, D. ed. 2002. Qualitative Research Methods. & Oxford: Blackwell.

Millar, R. (1998). &Rhetoric and reality: What practical work in science education is really for. In & `+

Wellington, J. ed., Practical work in school science: Which way now? (pp. 16 31). London: & Routledge.

Parkinson, J., 2002. & Reflective Teaching of Science 11-18. & London: & Continuum.

Weinberg, D., 2002. & Qualitative Research Methods, An Overview. & In: Weinberg, D. ed. 2002. Qualitative Research Methods. & Oxford: Blackwell.

Wellington, J., 1998. Introduction. &In & Wellington, J. ed. & 1998. & Practical work in school science: Which way now? (pp. 3 15). London: Routledge.

Wellington, J., 1998. Practical work in science. Time for a reappraisal. In & Wellington, J. ed. 1998. & Practical work in school science: Which way now? (pp. 3 15). London: Routledge.

Woolnough, B. Allsop, T., 1985. lt;i>Practical Work in Science. Cambridge: Cambridge University Press.

Appendix 1.

Table 1. (Abrahams and Millar, 2008)