Student to take home master (5)
I believe the answer is:
learn
'master' is the definition.
(thesaurus)
'student to take home' is the wordplay.
'student' becomes 'l'.
'to take home' becomes 'earn' (I've seen this before).
'l'+'earn'='LEARN'
(Other definitions for learn that I've seen before include "Pick up" , "Discover - study" , "Hear - memorise" , "Gain knowledge or skills" , "Study (at school?)" .)