Designing, Delivering and Assessing Practical and Laboratory-based Sessions

What are Practical and laboratory-based sessions?

Practical and laboratory-based sessions normally include a strong demonstration element, for example important techniques or how to use specific equipment, and they encourage students to have a go themselves.

It is often the case that practical or laboratory-based sessions begin with teaching basic skills, before students start applying them to investigate specific problems with the minimum of help or instruction. Figure 1 describes a number of typical practical tasks can be identified and categorised, from simple (closed) to more complex (open).

Figure 1: Types of practical tasks
1.	Tutor-led demonstrations	Usually done to demonstrate theoretical principles or explain standard instructions
2.	Exercises	From highly to, gradually, less structured experiments, designed so that students follow detailed instructions, learn specific manipulative and observation techniques and obtain known answers or results
3.	Structured enquiry	Structured experiments where students have responsibility for selecting resources, determining some parts of the methodology, and are given the opportunity to develop problem-solving and interpretative skills
4.	Open-ended enquiry	Students define a problem, choose and design an experimental methodology, consider its limitations, interpret results, and consider and discuss their implications – normally under time and/or resource constraints
5.	Projects	Carried out over a long period of time, and often in groups, they allow students to identify a problem, engage with, and explore, a topic in depth, and develop initiative and autonomy, as well as project and time management, and where appropriate, teamwork skills

What are they for?

Practical and laboratory-based learning sessions are likely to promote deep approaches to learning in many ways. They encourage students to:

• improve technical skills relevant to the subject
• improve understanding of methods of scientific enquiry
• reinforce theory with practice
• develop problem-solving skills
• nurture professional attitudes.

Practical and laboratory-based learning sessions create opportunities for self-, peer- and teacher-assessment of students’ understanding of links between practice and theory and of subject-specific competencies (Figure 2).

Figure 2: Possible outcomes of practical and laboratory-based learning sessions

Depending on the subject area covered and the level of study, practical sessions are likely to lead to achieving the following learning outcomes interpreting data, evaluating, formulating generalisations and testing theories developing enquiry-based approaches engaging with discipline-specific concepts, methodologies, instruments, techniques and procedures being familiar with health and safety issues and better able to assess potential risks appreciating and emulating the role of professionals, and experiencing and adopting relevant, appropriate and standard values, behaviours and interests in a range of situations keeping formal and accurate records managing time and developing autonomous learning skills making, and learning from, mistakes in a safe environment increasing one’s own confidence in a professional environment using communication (verbal and written) and negotiating skills effectively to share ideas and collaborate with others.

Planning and designing practical and laboratory sessions

Planning practical and laboratory-based work demands the same level of planning and preparation as for any other types of learning sessions. In particular, you should:

• establish aims and intended learning outcomes for the session and link them to the wider programme of learning
• choose and design appropriate, safe and feasible learning tasks
• design supportive resources, including instructions, procedures, a manual or worksheets.

Additionally, you should think carefully about:

• what students need to know to carry out practical tasks appropriately, and safely
• which skills students are expected to develop
• what equipment will be needed
• which problems students may encounter during the session.

Delivering practical and laboratory sessions

According to the Engineering Professors’ Council (1994), there are normally four main phases in a typical practical and laboratory-based sessions (Figure 3).

Figure 3: Four main phases
1.	Preliminary	Check the equipment and health-and-safety procedures
2.	Opening	Get the students’ attention. Check that they can hear and see you. Announce your intended learning outcomes for the session and show how the practical is related to the rest of the programme of learning. Describe the equipment to be used and how it works.
3.	Main section	Give clear instructions about how to use the equipment. Demonstrate how to perform the successive tasks safely and effectively. Mention possible mistakes that students should try to avoid making. Show them how to take, record, calculate, present and interpret results/data.
4.	Ending	Encourage students to ask questions. Review with them the expected learning outcomes for the session. Ask students to feed back their perceptions of the learning tasks and to summarise and discuss their main findings and possible problems and mistakes. Introduce the next session and suggest further work that students could undertake in their own time, whether or not it is part of some in-course summative assessment.

Figure 4 expands on the fourth phase of ‘ending’ a practical laboratory session with effective questions which can generate relevant, useful and meaningful interaction with individual students and groups. Questions should take account of students’ prior experience, challenge their knowledge and understanding, and help them to develop appropriate critical-thinking skills.

Figure 4: Examples of questions

Some examples of questions you could ask students to generate interaction and promote more active, deeper approaches to learning. What is going to happen if you do this? Why would you expect it to happen? What else could you do? What causes this? What exactly have you done? What were you trying to achieve? Why did you do it in this way? What could you have done differently?

Assessing practical and laboratory sessions

As any other type of learning activity, practical and laboratory-based work will be assessed. In fact, its importance should be reflected appropriately in its place in the overall assessment strategy, for example in the weight of the mark allocated in relation to the final mark for the module/programme.

Sometimes product is emphasised and bears a higher proportion of the overall mark for the practical component but, ideally, both process and outcome should normally be assessed.

Figure 5: Three main approaches to assessing practical work
Three main approaches to assessing practical work can be adopted.
1.	Evaluating some end product	In well-controlled practicals, the nature of the product may reflect the quality of the process, but in more open types of practical work, there may be many factors beyond the students’ control that weaken that link.
2.	Evaluating only the process	Using a template grid of previously established criteria, the teacher observes the students while they are carrying out the practical tasks. (Or the observation is done by other students in place of, or at the same time as, the teacher.) Students are made aware of the criteria prior to the start of the assessed activity.
3.	Evaluating the quality of process through marking written reports	When assessment of practicals becomes that of a written report, it is the quality of the report which tends to be measured rather than that of the work itself or the extent to which practical skills have been developed.

The traditional report will continue to have an important place in assessing practical and laboratory-based work, but alternative methods could be promoted that complement and enhance it.

Figure 6: Assessment methods for practical and laboratory-based work

Objective testing – which could be computerised Peer assessment – called critiques in some disciplines, and often used prior to final submission, i.e. as formative assessment Seminar or poster sessions, or exhibitions Individual or group oral presentations, vivas or interviews with an individual or a panel of assessors Direct observation of students’ individual practical work Written examination questions or multiple-choice questionnaires based on methodologies and findings from practical activities Students’ reflection about, or interpretation and critical review of, video material or computer-based data from an experiment Portfolio-based evidence of specific competencies Reflective journal, diary or log book Self assessment.

As for any other teaching methods, practical and laboratory-based sessions should aim to create a suitable environment which maximises learning and achieving learning outcomes. Careful planning, learning-centred delivery, valid and meaningful assessment strategies and skilled lesson management are essential components of a systematic approach to designing this type of learning experience.