Numpty finishes off final nine pages after school (7)

I believe the answer is:

schlepp

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'school' is the definition.
Both the definition and answer are singular nouns.
Maybe they are linked in a way I don't understand?

I don't understand the remainder of the clue.

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(Other definitions for schlepp that I've seen before include "Stupid chap" , "Someone ignorant" , "someone unimportant" , "Pull along" .)

I've seen this clue in The Times and The Sunday Times.

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