Favoured pupil (8,3)
I believe the answer is:
teachers pet
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">favoured pupil</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for teachers pet that I've seen before include "(Mocked) school favourite" , "goody-goody" , "Student of form favoured" , "Favourite in form" , "Class favourite" .)