Abstain from school in little rising (6)
I believe the answer is:
eschew
'abstain from' is the definition.
(to eschew something is to avoid it)
'school in little rising' is the wordplay.
'school' becomes 'sch' (abbreviation).
'in' is an insertion indicator.
'little' becomes 'wee' (similar in meaning).
'rising' says the letters should be written backwards (going up in a down clue).
'wee' written backwards gives 'eew'.
'sch' put inside 'eew' is 'ESCHEW'.
(Other definitions for eschew that I've seen before include "Abandon" , "'Avoid, stay away from (6)'" , "Deliberately avoid" , "Avoid,shun" , "Don't use" .)