School-Ready. The Pop Quiz backpack by Herschel Supply Co. was built for the life of commutes, university lectures, and hanging around school cafeterias. It’s made of durable polyester fabric, has Herschel’s signature soft inner lining, and comes with a bottom that’s reinforced with a rugged eco-friendly material. The main compartment holds most of the packs’ 20L storage space and has a padded/fleece-lined 15” laptop sleeve, along with fleece-lined sunglass/accessory pocket. The front of the Pop Quiz has an organizer pocket that comes with a key clip. It’s also decorated with the signature woven Herschel label.