School now, then this? A learner's acting alone (10)
I believe the answer is:
unilateral
'acting alone' is the definition.
(acting on one side or independently)
'school now then this? a learner's' is the wordplay.
'school now then this?' becomes 'unilater' (if school now, then university later).
'learner' becomes 'l'.
'unilater'+'a'+'l'='UNILATERAL'
(Other definitions for unilateral that I've seen before include "affecting only one person out of several" , "One-sided" , "Done only by one side" .)