Enabling students to learn from practical work

It is time to think critically about how best to teach practical work. This is particularly the case for those teaching A-level courses now that assessed practicals have gone, and now we know the rules of engagement for required practicals. The explicit focus on practical skills within written exams means students need a deep understanding of the underlying chemistry as well the practical.

I have been developing a practical curriculum with students’ understanding of practical method and links to theory at its heart. The approach is completely different to the way we used to prepare students for assessed practicals. Under that system, designing practicals as similar as possible to the ‘real thing’ meant students could simply repeat themselves under timed conditions. This, however, lacks emphasis on understanding.

To design a coherent practical course focused on student learning rather than performance, I advocate three key principles that mean ripping up the materials provided by exam boards, designing better ones, and putting the burden of effort squarely onto students’ shoulders – they can handle it. 

1. Balance content and practical skills with a range of activities

Consider what additional practical work would support students’ learning. Within each A-level curriculum topic, there tends to be just one practical required by exam boards. However, this shouldn’t be the only practical your students carry out in each topic.

For ideas about practical content you can use as part of teaching a topic, identify practicals in exam papers that differ to the required one. For example, not all moles questions are based on straightforward titrations, so why stick to titrations?

Identify skills a required practical focuses on, and create more opportunities to develop those skills. For example, if a required practical emphasises quantitative data analysis, then supporting practicals beforehand should focus students on planning, assessment of risk, or processing qualitative data. Without this shift of perspective, students only gain surface learning of the underlying ideas.

As an example, you could carry out the following sequence of practicals to balance learning energetics with learning data analysis skills: 

2. Adapt practicals to link observations and ideas

To really get students thinking, don’t be afraid to adapt practical sheets provided by exam boards to match students’ needs. All sheets give the full method, safety and analysis questions, which undermine students’ opportunities to show they have attained the common practical assessment criteria.

There are a number of quick ways to edit the practical sheets.

• Delete the method so students can fill it in themselves.
• Edit the method so it contains mistakes for students to correct.
• Give students a range of apparatus to select from.
• Provide the method, but ask students to determine the analysis they will carry out.
• Give students chemical hazard information and get them to fill in the safety information.

Deeper learning results when students link their experimental observations to their theoretical understanding. Use the framework below during department meetings to discuss, evaluate and improve a required practical. You will all benefit from a range of ideas and responses. 

3. Make students do the difficult bits

Get students to do the thinking teachers usually do before a lesson, ie which concentration of acid should I order for this titration, or what is the maximum temperature for this rates practical? When I plan practical work for students, I deprive students of the opportunity – yes, the opportunity – of doing that for themselves.

Run practical pre-labs, as ‘real’ scientists would do. Give students the wrong concentration so they have to work out the right dilution from a few rough titrations. Let them do some trials instead of telling them what concentrations of peroxodisulfate get reasonable times in a clock reaction.