Youngster taking course at Oxford got his head down (6)

I believe the answer is:

kipped

'got his head down' is the definition.
(slept)

'youngster taking course at oxford' is the wordplay.
'youngster' becomes 'kid' (synonyms).
'taking' is an insertion indicator.
'course at oxford' becomes 'PPE' (Philosophy, Politics and Economics).
'kid' enclosing 'ppe' is 'KIPPED'.

I've seen this clue in The Guardian.

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