Every August, before the students arrive, the same question returns: how much of this year should I plan now? In my first year I planned almost nothing beyond the fortnight ahead, and spent the year feeling hunted. In my second I planned everything, and spent the year watching my beautiful schedule collide with reality. Two curricula I teach under pull in opposite directions on this, and the tension between them is instructive.
The IB leans one way. Its philosophy is inquiry-driven and concept-based: the student's questions are supposed to matter, the teacher is a facilitator of exploration rather than a deliverer of content, and a rigid twelve-week plan sits awkwardly with a classroom that is meant to follow genuine curiosity. IGCSE pulls the other way. There is a syllabus, an exam board, a defined body of content, and a date in May when a child sits a paper covering all of it. Nobody at Cambridge asks whether the class's inquiry happened to reach the topic of quotation analysis by exam day.
Both cultures have a point, and both have a failure mode. Pure week-by-week planning is responsive but incoherent: lessons become a series of disconnected events, and the teacher discovers gaps in coverage when it is too late to fill them. Pure advance planning is coherent but brittle: the plan was written for a class that existed in August, not the one that actually turned up, and it cannot accommodate the discovery that half the class never really understood paragraph structure.
The research, read fairly, supports both instincts. Wiggins and McTighe's Understanding by Design made the case for "backward design" two decades ago: start with the desired results, decide what evidence would show students have got there, and only then plan the learning experiences. It is an argument for long-term planning in the strongest sense — not planning every lesson, but fixing the destination and the checkpoints before the journey begins. Meanwhile, Black and Wiliam's landmark 1998 review of formative assessment found robust evidence that teaching which adjusts in response to evidence of student learning produces substantially better outcomes. Adjusting requires slack. You cannot respond to what the class shows you on Tuesday if every Tuesday until December is already spoken for.
The case for planned flexibility
My working answer is to plan the year in full, but build in roughly 30 per cent flexibility as a deliberate structural feature rather than an admission of failure. Concretely, this means the long-term plan fixes three things and leaves the rest open.
First, the destination is fixed: the assessments, the exam dates, the final products. This is Wiggins and McTighe's first stage, and it is non-negotiable, because students deserve to know where they are heading. Second, the sequence of units is fixed, because skills build on each other and I have thought about the order. Third, the major checkpoints are fixed — the moments where I gather evidence about whether the class is actually learning, not merely being taught.
Everything else is held lightly. Within each unit, roughly a third of the lessons are planned in outline only, to be designed properly the week before, in the light of what the checkpoints have shown. If the class is flying, those lessons extend and deepen; if the class is stuck, they reteach and practise. This is where the IB instinct earns its place inside an IGCSE structure: responsiveness is not the opposite of planning, it is what the planning is for. A plan that cannot absorb the discovery that students misunderstood something is not a plan, it is a fantasy with dates on it.
The 30 per cent figure is not sacred — it is a discipline, and the number matters less than the habit of reserving capacity. Teachers under exam pressure tend to let flexibility shrink to zero, filling every lesson with content delivery, which is precisely when the plan stops serving the students and starts serving itself.
A teacher I respect once told me that planning is like packing for a long walk: you fix the route and the checkpoints, but you leave room in the bag for what you find on the way. I would put it less picturesquely. The plan is a hypothesis about how this class will learn, and hypotheses exist to be revised against evidence. Write the plan. Keep a third of it soft. Then pay attention.