This was the gratifying verdict of a lesson spent solving molar calculations in groups. Unfortunately, the strategy was only effective for one of the four groups.

I decided to put the year 12 class (age range: 16 to 17) in groups for two main reasons. Firstly, there are several strong students in the class who finish in seconds questions that their classmates are still wondering how to begin. Secondly, a small group of less mature students had taken to sitting together at the back and heckling. Dividing them into groups was supposed to separate this challenging clique while also creating opportunities for stronger students to peer tutor their classmates.

Assigning roles is said to be an effective way of conducting group work, so that each student feels clear about what is required of them. I couldn’t find any suggested roles for chemistry-specific group work so I made up my own: 1) checker 2) calculator 3) equation and conversion specialist and 4) framework writer. This last required the most explanation. What teacher has not marked an answer which constitutes nothing more than a quagmire of numbers? The framework writer’s job was to label each number, eg: this is the volume of carbon dioxide, this is the number of moles of carbon dioxide, and so on. Similarly the equation and conversion specialist had to write out each equation in the correct terms and write out each conversion, eg: 100kPa = 100000Pa. The checker was supposed to check they agreed with everything and midway through I gave checkers another job, too: to make a note of any mistakes that were made. Other roles I considered were measurement to moles converter and stoichiometry expert.

So how did it pan out? One group worked really effectively. They stuck to their roles, worked as instructed and made good progress. Other groups did not perform so well. In one group the strongest student was determined simply to do everything and struggled with the task of working collaboratively. In the worst cases groups were held up by the refusal of individuals to do their share of the work. This is an evergreen problem in group work.

Looking back I see the mistakes I made. Several people had suggested getting students to write in marker pens on sugar paper or some equivalent. I made the decision to have them write on single A4 sheets of paper which are simply too small for more than one person to work on at any one time. Sugar paper was a good idea not only because all group members could simultaneously access it but would also facilitate something else that would have been sensible – having groups present their work. Knowing that work has to be presented is a great motivator for those students who need pushing to stay on task. On that point there’s another even more effective strategy that I wish I’d thought to use: having students anonymously grade each other’s performance. Finally it was a mistake to let the activity run for the whole lesson. I will persist with group work but next time I will do a short burst of 10 or at most 20 minutes. @flatlander20 suggested assigning groups to find the deliberate errors in worked calculations. The more structured nature of the task would definitely promote more effective group work, but the downside is it needs more planning.

All of these teething problems meant I couldn’t effectively evaluate my suggested roles for each of the group members. Having said that, when it worked, it really worked. The high performing group turned in a beautiful solution with every step labelled, with their mistakes summarised and with the correct answer. I think the roles warrant further investigation, but the motivational strategies are definitely more important going forward.