One caught after lesson producing standard work (7)
I believe the answer is:
Here is my best explanation:
'standard work' is the definition.
'one caught after lesson' is the wordplay.
'one' becomes 'i' (Roman numeral).
'caught' becomes 'c' (cricket abbreviation).
'after' means one lot of letters go next to another.
'lesson' becomes 'class' (I've seen this before).
'ic' put after 'class' is 'CLASSIC'.
'producing' is the link.
(Other definitions for classic that I've seen before include "High quality", "Serving as a standard - of the highest quality", "The Derby, for instance", "Timeless-quality work; a race", "Very typical", "Race, eg Derby", "Model", "Very good example of its kind", "The Derby or The Oaks, for example" and "Important horse race".)