Understanding provided by home schooling (9)
I believe the answer is:
intuition
'understanding' is the definition.
(I've seen this before)
'by home schooling' is the wordplay.
'by' is a charade indicator (letters next to each other).
'home' becomes 'in' ('he's home' can mean 'he's in').
'schooling' becomes 'tuition' (both can mean teaching).
'in'+'tuition' is 'INTUITION'.
'provided' is the link.
(Other definitions for intuition that I've seen before include "Hunch" , "Suspicion" , "Unjustified belief" , "Ability to understand immediately" , "Instinctive knowledge" .)