Teacher with good ability to listen produces mortarboard? (8)
I believe the answer is:
headgear
'mortarboard?' is the definition.
(mortarboard is a kind of headgear)
'teacher with good ability' is the wordplay.
'teacher' becomes 'head'.
'with' is a charade indicator (letters next to each other).
'good' becomes 'g' (abbreviation).
'ability' becomes 'ear' (ear is a kind of ability).
'head'+'g'+'ear'='HEADGEAR'
'to listen produces' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for headgear that I've seen before include "Hats, bonnets, caps etc" , "Aged hare? (anagram)" , "bowler perhaps" , "which sits on top of mine?" , "Hats, helmets etc." .)
