Criticise adopting student's scheme (4)
I believe the answer is:
plan
'scheme' is the definition.
(thesaurus)
'criticise adopting student's' is the wordplay.
'criticise' becomes 'pan' (informal term meaning to criticise heavily).
'adopting' indicates putting letters inside.
'student' becomes 'l'.
'pan' going around 'l' is 'PLAN'.
(Other definitions for plan that I've seen before include "Scale drawing of a structure" , "Design; map" , "Project" , "Stratagem" , "Devise a strategy" .)