Recycling and Review
Deliberate reintroduction of previously taught language across lessons, units, and terms, so that items meet learners repeatedly in different contexts rather than appearing once and being assumed to have been learned. Recycling is the design-time response to the well-documented finding that single encounters with a new word or structure rarely produce stable knowledge — multiple spaced encounters do.
Why it matters
Paul Nation's synthesis of the vocabulary research argues that learners need many encounters with a word before they know it well enough to use it, and that those encounters must be spaced and varied to convert recognition into productive knowledge. Estimates of the number of encounters required vary by item difficulty, learner level, and depth of knowledge sought, but the qualitative finding is consistent: a word taught and never revisited fades; a word revisited across several distinct contexts persists. The same logic applies to grammar, formulaic chunks, and discourse patterns, although the encounter counts and the form they take differ.
This makes recycling a syllabus property, not a teacher reflex. Whether learners meet last week's target items again next week depends on what next week's lesson contains, which is fixed at the Scheme of Work stage. A scheme that introduces ten items per unit and never revisits them produces a course in which learners are perpetually meeting new material on the surface and accumulating little underneath. A scheme designed for recycling carries earlier items into later units as background vocabulary in reading texts, as ingredients in speaking tasks, and as the operating language of classroom routines.
Designing for recycling
Effective recycling is layered. Within a lesson, controlled practice followed later by freer practice forces a second encounter under different conditions. Within a unit, a milestone task at the end requires items introduced in earlier sessions. Within a term, cumulative review sessions surface recurring patterns across units. Across the year, the same lexical sets reappear in new genres and at higher levels of demand — a topic introduced for description in week three returns for argument in week twenty.
The principle generalises beyond vocabulary. Skill strategies — predicting in reading, paraphrasing in writing, signposting in speaking — also need spaced revisitation if learners are to internalise them. Course-level reviews work less well when they repackage the same exercise type and better when they require the same language under different task demands.
Recycling and review are distinct. Review surfaces what has been taught and checks retention; recycling embeds prior items inside new tasks so they are used rather than tested. A strong syllabus does both.