Practical work in science lessons

It is important that science teachers are sceptical about the benefits of practical work.

For too long, I assumed that doing practical work in science classrooms was a good thing without considering why I thought this. While I haven’t changed my mind on the importance of practical work, I have, over the years, developed my justification for it.

At a fundamental level, practical work is important in science lessons because it provides a link between the physical world that pupils can touch, smell, see and taste and the scientific ideas that they can’t. This ‘bridge’ facilitates a cognitive union, or process of meaning making, whereby students learn to connect the scientific idea to the physical phenomena it explains, and vice versa. Without such a link, science can remain a collection of abstract ideas to students, lacking any explanatory purpose or relevance. At the same time, the physical world continues to be less interesting and meaningful than it could be with a scientific perspective. I suppose this could be seen as a pedagogical justification for practical work but for me it runs deeper than that. Practical work and learning science are inseparable because to know science requires pupils to be able to transverse this ‘bridge’ in their mind. By doing so they are able to connect, and reason about, these two entirely different worlds, almost simultaneously, in ways that alter the significance of both.

This isn’t to say, however, that this cognitive union is an inevitable consequence of students carrying out practical activities. Research is clear that this isn’t always the case. Just that, when it works, practical work can have a profound effect on the quality of what students learn.

Beyond this fundamental justification for practical work lie more utilitarian purposes that can be linked to Derek Hodson’s (2014) purposes of science education.

Practical work can help pupils to:

learn science e.g. learn about the concept of dissolving
learn about science e.g. learn how scientists classify organisms or what anomalies are
learn how to do science e.g. learn how to carry out a specific scientific enquiry

Looking at the purposes listed above, practical work is interesting because it can serve slightly different roles in learning science. For example, it can play a pedagogical role e.g. illustrating the process of dissolving or instead can form a goal of the curriculum e.g. knowing how to use a quadrat to sample the population of daisies in a field. I’ve written about this difference here if you want to find out more.

While most pupils enjoy practical work (75% secondary-aged pupils) and want to do more (71%), this is not always the case (Sharpe and Abrahams, 2020). Findings from research in England show that pupils need to see a value in practical work in relation to the final examination in order to have positive attitudes towards it (Sharpe and Abrahams, 2020) and that without this the affective value of practical work
can decrease as pupils approach their final exams.

Here, Robin Millar considers why practical work is important in science. To what extent do you agree with this perspective?

Conceptual versus procedural demand

One of the challenges of practical work is that pupils can become overwhelmed by too much new information at once. Ideas on working memory and cognitive load can be helpful here to understand these challenges.

I came across this graph at the National STEM Learning Centre that can be helpful to explore this difficulty by considering two dimensions of demand: conceptual and procedural. Each quadrant represents a possible level of procedural and conceptual demand that a particular activity can place on a student.

Where do you think each practical sits?
How can you modify the conceptual and procedural demands of each practical to match the students in your class?

Altering the demand of tasks can involve modifying the practical but it is important to consider the role of prior knowledge and skills too. The success of a practical is as much about the prior learning that took place in preparation as it is about the practical lesson itself. This has important implications for curriculum design too in that the demand of any practical activity can be increased or lessened by what came before. In another words, if a practical activity is proving difficult for students the cause of the problem may well lie in the previous unit/term or year.

One solution is to reduce complexity by using integrated instructions. David Patterson’s paper outlines how integrated instructions can help students know what to do during a practical activity. It’s worth bearing in mind, however, that a goal of the curriculum may be for students to follow a method. In which case, there will come a time when they will need to complete this successfully, irrespective of the cognitive demand involved.

Other frameworks to think about practical work

A more recent publication by the Gatsby foundation on Good Practical Science has defined five purposes of practical work as:

to teach the principles of scientific inquiry
to improve understanding of theory through practical experience
to teach specific practical skills, such as measurement and observation, that may be useful in future study or employment
to motivate and engage students
to develop higher level skills and attributes such as communication, teamwork and perseverance

Aspects 1-3 are similar to those I’ve outlined above however there are two additional ones that relate to motivation and transferable skills such as teamwork.

Whatever framework you use to consider the purposes of practical work, what’s important is that you approach any practical activity by justifying its purpose – is it chiefly a pedagogical one in helping students to learn a particular concept or part of a skill or does it form a goal of the curriculum in its own right. Then, I think it’s about assuring yourself that the curriculum has done what it can to enable students to be successful in that task but making sure that students aren’t being expected to learn too many things in too shorter time.

Practical work in science lessons

Conceptual versus procedural demand

Other frameworks to think about practical work

Further reading