School embracing popular conclusion (6)
I believe the answer is:
finish
'conclusion' is the definition.
(finish is a kind of conclusion)
'school embracing popular' is the wordplay.
'school' becomes 'fish'.
'embracing' means one lot of letters goes inside another.
'popular' becomes 'in'.
'fish' placed around 'in' is 'FINISH'.
(Other definitions for finish that I've seen before include "Bring to an end" , "perfection" , "Refinement in social graces" , "Complete (6,3) - See 16" , "Conclude, end" .)