Be paid to study but not back in school (4)
I believe the answer is:
earn
'be paid' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for earn that I've seen before include "Acquire money by labour" , "Gain credit from" , "Make; deserve" , "Receive by effort" , "Gain by work or effort" .)