Target and Walmart are the places to stock up on year round school or program supplies -

spiral bound ruled notebooks  and glue sticks each 10cents; crayons 25 cents, peechee style folders in solids or designs for 15 cents, markers for 1.00, stackable plastic pencil/supply boxes for 60 cents each.  I use them for "work boxes", keeping household supplies organized, sorting boxes for my childs OT manipulatives, game parts, etc.  

Sales may end by end of August - but this IS the time to stock up on all of your office/school needs.