Why mini-plenaries are a waste of time

Plenary is an interesting word. It originally meant absolute, without reservation or qualification. The pope used to offer plenary indulgences to crusaders absolving them in advance of any sin they committed in the defence of the Holy Land.

Later it came mean full, complete or pertaining to all. A meeting or assembly to which all were obliged or expected to attend would be called a plenary. Nowadays, conferences often have plenary sessions which sum up themes and draw disparate threads together. From here the word has leapt into education parlance as a mechanism for ending lessons in a way intended to ensure that all students are clear on what they were meant to have learned.

A plenary isn’t a bad way to end a lesson. That’s not to say it ought to be a requirement – there’s certainly insufficient evidence to compel all teachers to end every lesson with a plenary – but it’s probably a good idea to round off and summarise to remind students what the point was supposed to be. What’s unnecessary are plenary activities, but these became, until relatively recently, educational dogma.

Look, for instance, at the state of this DfE guidance from 2002. Teachers are offered the following suggestions for involving students in plenary activities:

Now, while you could do any of these things, the consequence will be that you have less time to  spend on actually teaching students content. It’s not that these sorts of plenary activities are bad, just that they come at a cost.

This cost is compounded when teachers are advised, or coerced, to included ‘mini-plenaries’ at various points through out their lessons. If these were just ad hoc checks on students’ understanding, all would be well, but when the expectation is an activity, we run into problems.  In the DfE guidance linked to above, teachers are told, “Plenaries are also useful part way through a lesson: staging posts when the teacher draws the class together, crystallises understanding and directs the class to the next phase of work.” Possibly, but the more time you spend drawing things together, crystalising understanding and directing classes to the next phase of work, the less there will be to draw together, understand and direct towards.

If the point of the plenary is help students remember what’s important, then it will serve a useful purpose. The trouble is, remembering something you’ve just been taught is a low bar over which to step. As I’ve explained before, learning is distinct from performance. If we invest lesson time on improving students’ performance at best we will be valuing mimicry, but at worst we might end up inadvertently undermining long-term learning. Aside from the opportunity cost, mini-plenaries are far more likely to undermine efforts to get students to retain or transfer important knowledge and skills.

Other poor reasons for using mini-plenaries are the mistaken beliefs that they prove progress or that they make lessons engaging. I explain here the nonsense of proving progress in lessons and here I argue against the use of engagement as a proxy for learning. There’s also the question of why on earth you’d think a mini-plenary was more engaging than rich, inherently fascinating subject content.

My advice, for what it’s worth, is to do away with plenaries and instead begin lessons with a recap of what you hope students will have remembered from previous lessons. Research into the testing effect tells us that the best way to go about this would be to give students low stakes quizzes to undermine the illusion of knowledge and provide a more accurate awareness of ignorance. Multiple-choice questions are an efficient way to go about this.

To clarify:

• Pausing to check students have understood is an integral part of teaching. There is no earthly need to refer to this as a mini-plenary: let’s just call it teaching.
• Not all checking activities are bad per se. Some may be excellent, but all will have a cost. Make sure the cost is worth it.
• If you want to avoid privileging short-term performance over learning, it’s probably better to wait at least until next lesson to see what students have retained.
• No mini-plenary activity, whatever it’s called, should ever be mandated. Any school leader who takes this approach is either ignorant or stupid. Neither ignorance nor stupidity are desirable leadership qualities.