Female teachers having papers returned first (7)
I believe the answer is:
'female' is the definition.
(distaff can mean relating to women)
'teachers having papers returned first' is the wordplay.
'teachers' becomes 'staff' (school staff).
'having papers' becomes 'id' (I can't justify this - if you can you should believe this answer much more).
'returned' is a reversal indicator.
'first' means one lot of letters go next to another.
'id' in reverse letter order is 'di'.
'staff' put after 'di' is 'DISTAFF'.
(Other definitions for distaff that I've seen before include "Wool spinning spindle" , "concerning women" , "Stick holding wood, in spinning" , "female stick" , "The female side in a family tree" .)