Case involving United closed — a learning experience (8)
I believe the answer is:
tutorial
'a learning experience' is the definition.
(tuition session)
'case involving united closed' is the wordplay.
'case' becomes 'trial' (I've seen this before).
'involving' is an insertion indicator.
'united' becomes 'U' (abbreviation).
'closed' becomes 'to' (as in a door closed to).
'u'+'to'='uto'
'trial' placed around 'uto' is 'TUTORIAL'.
(Other definitions for tutorial that I've seen before include "Session with a private instructor" , "University lesson" , "Period of teaching as from college lecturer" , "University study period" , "Rail tout (anag)" .)