Harmonise with piece of music on curriculum (6)
I believe the answer is:
concur
'harmonise' is the definition.
(thesaurus)
'piece of music on curriculum' is the wordplay.
'piece of' indicates the answer is hidden within the clue.
'CONCUR' is hidden within 'music on curriculum'.
'with' acts as a link.
(Other definitions for concur that I've seen before include "Agree, assent" , "share the same opinion" , "Agree or happen together" , "Stone pile" , "Express agreement" .)