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Learners must achieve a level of mastery in prerequisite knowledge/skills/methods
before moving forward to learn subsequent knowledge/skills/methods.
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- a better memory effect: when learners return to the same topic the next time, they have the prerequisite work "at their finger tips",
- a better synthesising effect: learners can build, as their higher attaining peers do, on solid foundations, they can plan, make links and synthesise their own methods as well as be more ready to access efficient methods taught by the teacher,
- a self-esteem building effect: since when learners return to a topic they soon realise that they can make progress, they are more keen to enjoy the pride in a job well done from learning and making progress.
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