Discontented tutor that is teacher assessed for suitability (5,2)
I believe the answer is:
tried on
'assessed for suitability' is the definition.
(as in trying on clothes)
'discontented tutor that is teacher' is the wordplay.
'discontented' says to hollow out the word (remove centre letters) (the word's contents are removed).
'that is' becomes 'ie' (short for Latin 'id est', 'that is').
'teacher' becomes 'don' (don is a kind of teacher).
'tutor' with its centre taken out is 'tr'.
'tr'+'ie'+'don'='TRIED ON'
(Other definitions for tried on that I've seen before include "tested for suitability" , "Tested the fit of (a garment)" , "Checked shirt perhaps" , "Donned a garment to see if it suited" .)