What is an effective use of class time for maths - reinforcement, learning, support?

Preparatory questions and links:

Focusing questions:
How much do you plan time for lessons and how often does the plan work?
Does age or school year make a difference? How?
Do some things need more reinforcement than others? If so, does this suggest mis-used time earlier?
Do you see teaching as being a combination of these three components or something which needs its own allocation of time?
Are these three elements separable, if so, what differences in methodology would you use for each of them?
Are all three equally important or do you need to continually adjust the balance between them?

(Provided by @ColinTGraham)

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Threaded discussion from Thursday,16th September 2010 -
Threaded discussion from Monday, 20th September 2010 -

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