Bag for school books (7)
I believe the answer is:
satchel
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bag for school books</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 satchel that I've seen before include "Bag with a flap and strap" , "Shoulder bag as for schoolbooks" , "Carrier for school books" , "Get school item" , "Schoolchild's carrier" .)