In popular culture, the image of a scientist is often coupled to laboratory work, where a person in a white lab coat carries out some kind of exciting, ground-breaking experiment. The reality of course is much more mundane — not all scientists wear white coats and the majority of laboratory work is routine — nevertheless, laboratory work does indeed form an important part of the work of many scientists and as such is included in the majority of undergraduate science programmes. Whilst the position of laboratory work in science degrees is unchallenged, the effectiveness of this kind of activity is generally not well understood. How should participation in laboratory work be organised and what are the effects on wider student learning?
Part of the problem when deciding what to prioritize in the laboratory lies in a fundamental dichotomy in how we traditionally think about the role of student lab work. On the one hand, we want students to understand the processes of experimentation, whilst on the other, we see an opportunity to practically investigate concepts that we have introduced theoretically in lectures. In physics for example, the undergraduate laboratory has traditionally been seen as the place where students consolidate knowledge gained in lectures. Experimentation skills, it was claimed, would naturally be developed along the way. However, in recent years the validity this ‘two for the price of one’ approach has been challenged. It has been argued by a number of authors that the principal role of laboratory work should be to teach experimentation itself in order to help students to develop expert-like habits. Such revised laboratory courses have signalled a movement away from so-called ‘cookbook’ experiments where students follow a set of instructions, towards more open-ended tasks where students design their own experiments, evaluate the results and make iterative improvements (Handelsman et al 2004, Monteyne & Cracolice, 2004; Brownell et al 2012). Naturally, one side-effect of the introduction of this type of approach is a reduction in the number of topics that can be reasonably covered in undergraduate physics laboratories. Thus, whilst the benefits of reformed laboratory work have been confirmed by a number of researchers, questions have been raised in some quarters about the effects of the reduced content coverage on wider physics performance. In a study reported in Physical Review a controlled trial of the two approaches was devised where students on the same programme were randomly assigned to either a traditional laboratory course or a revised course focussed on the teaching of experimentation. As predicted, the experimentation cohort showed positive effects on student motivation and expert-like thinking, but crucially, the researchers could also show that there was no measurable difference between the two groups in terms of their performance in formal written examinations of the lecture-based content in theoretical courses. Moreover, students who took the traditional content-reinforcement labs showed a measurable deterioration in their attitudes to experimental physics and tended not to engage in high-level scientific thinking in their laboratory work, even when the structured questions specifically encouraged this approach.
The paper adds weight to the argument for less content coverage and more open-ended tasks in physics laboratories, and encourages a discussion about the aims of laboratory work in undergraduate degree programmes.
Comment: The benefits of open-ended lab-work have been continually documented for over thirty years now. However, despite the reported positive effects of students focussing on experimental design and the overwhelming evidence that students do not learn well in traditional laboratory work, prescriptive tasks continue to be the dominant form of choice on many courses. It is tempting to think of this lack of change as another instance of Kuhn’s (1962) Structure of Scientific Revolutions (where disciplines are characterized as reluctant to change even in the face of strong evidence) however the truth may be much more pragmatic. A prescriptive lab, once written can be recycled time after time and is independent of who is running the lab — this means almost ‘anyone’ can take over at short notice without any particular pedagogical training. Open-ended labs, however, require a different type of approach in order for them to function as intended. It is usual for those participating in this sort of initiative to have had some kind of specialized training to understand the thinking behind the methods used (see for example the description of the Integrated Science Learning Environment ISLE developed at Rutgers). Training takes time and money and flexibility is naturally reduced when only trained staff can run the labs.
Finally, there is another, less flattering potential explanation for why prescriptive labs retain their popularity despite evidence that they are counterproductive — as university lecturers we are naturally at the forefront of our research areas, but our knowledge of the findings of discipline-based educational research can often be quite sketchy.
Interested in discussing this further?
CeUL is offering workshop on the design of student laboratory tasks 09:00—12:00, March 11, 2022. Find out more here: Workshop: Laboratory tasks as an instructional strategy in science education
Text: John Airey, Department of Teaching and Learning
Keywords: physics education research, laboratory work, experimentation, assessment, learning environment, expert-like thinking, motivation, attitudes, beliefs.
Read more
Brownell, S. E., Kloser, M. J., Fukami, T., & Shavelson, R. (2012). Undergraduate Biology Lab Courses: Comparing the Impact of Traditionally Based" Cookbook" and Authentic Research-Based Courses on Student Lab Experiences. Journal of College Science Teaching, 41(4).
Kuhn, T. S. (1962). The structure of scientific revolutions: University of Chicago press. Original edition.
