Fool, at university, to revise (3,2)
I believe the answer is:
mug up
'revise' is the definition.
(I've seen this before)
'fool at university' is the wordplay.
'fool' becomes 'mug' ('mug' can be a synonym of 'fool'**).
'at university' becomes 'up'.
'mug'+'up'='MUG UP'
'to' is the link.
(Other definitions for mug up that I've seen before include "do emergency study" , "Learn (subject) quickly" , "Swot hard" , "Cram" , "Study hard" .)