Old coin found in educational establishment (5)
I believe the answer is:
ducat
'old coin' is the definition.
(I've seen this before)
'in educational establishment' is the wordplay.
'in' indicates the answer is hidden within the clue.
'DUCAT' is hidden in the letters of 'educational establishment'.
'found' acts as a link.
(Other definitions for ducat that I've seen before include "ready no longer" , "Former European gold coin" , "piece of gold" , "Old Italian coin" , "Money no longer" .)