Pencils have been swapped for stylus pens; hardcovers have morphed into e-books; thermoses have become tumblers. School supplies have changed (Trapper Keeper, anyone?), but the way students carry them has not. Backpacks are big business, with more than 175 million sold each year. And for good reason: They’re durable, roomy, and functional. A plain black pack allows students to blend in—or stand out, with the addition of patches, pins, ribbons, and keychains. From JanSport to Herschel, Eastpak to North Face, these are the things they carried.