We compared prices on five basic classroom supplies -- pencils, loose-leaf paper, glue sticks, crayons, and three-ring binders -- at Costco, Walmart, Target, and Amazon. Three of the five items were cheapest when bought in bulk at Costco. Dixon Ticonderoga HB #2 pencils come in a box of 96 for $15.39, or 16 cents each, a savings of up to 68 percent over the other stores. A 12-count package of 1-inch view binders cost $20.79, or $1.73 for each three-ring binder, compared with $2 to $2.74 elsewhere (for the Office Impressions or Avery brand). Maybe nearly 100 pencils or a dozen binders sounds like overkill, but these bulk buys can be split among everyone in the family, or with a neighbor or friend.