Accompanying a student, nevertheless (6)
I believe the answer is:
withal
'nevertheless' is the definition.
('withal' can be a synonym of 'nevertheless')
'accompanying a student' is the wordplay.
'accompanying' becomes 'with' (I've seen this before).
'student' becomes 'l' (as in L-plates for learner drivers).
'with'+'a'+'l'='WITHAL'
(Other definitions for withal that I've seen before include "Despite that, notwithstanding" , "In addition (archaic)" , "nevertheless" , "as well" , "moreover" .)