•Beverage berths. Originally designed for athletes and outdoor enthusiasts, bags with built-in "hydration bladders" or attachments for sports bottles are becoming more common. JanSport introduced its $50 Big Squirt this season with a straw-like tube that'll screw onto anything from small-mouth water bottles to wide-mouth sports drink bottles.
•Packs for women. North Face's idea of a woman's pack used to be to make it pink. Now it has the $69 Isabella pack designed to fit the narrower shoulders and waist and wider hips of a woman's torso.
•Air cushioning. Nike is putting the same air technology used in its sneakers into backpack straps. The straps of several of its Edge Elite packs have air-filled chambers to make them more comfortable. Price: up to $90.
•Artsy looks. JanSport has figured out how to get its bags into trendy Urban Outfitters urbn stores: Hire street artists to design them. Its Artist series targets teens with cool illustrations etched into limited edition bags. Price: $45.
•Eco-friendly packs. A Juice Bag, priced at up to $300, is made from recycled soda bottles and has a solar panel to charge cellphones and iPods. "We give students the power to stay connected while they roam," says Henry Gentenaar of bag maker Reware.
•Packs with wheels. They're big among schoolchildren ages 7 to 10, says Pam Jones, senior pack developer at L.L. Bean. But beware: Some schools ban them for fear of damage to floors. The wheel systems can save on lifting, but they add weight to the packs.
•"Full disclosure" packs. For security reasons, some schools require see-through bags such as JanSport's $35 Mesh Pack to show what students are packing.
•The messenger look. These shoulder bags with fold-over flaps are big among some fashion worshipers. Tumi's hot-seller is its $175 messenger. Timbuk2 sells a $95, blank canvas messenger for artsy students to customize.
•Personalized bags. L.L. Bean has sold packs personalized with embroidered lettering for more than a decade. Its advertising used to show packs with kids' names on them, but examples now show only monogrammed initials. It still will embroider a name if a buyer wants it, but it stopped promoting the idea two years ago because of safety concerns about revealing kids' names to strangers.
Perhaps a better way to personalize a pack is to do what Laura Jabczenski did with her Skullcandy bag: fill the white space with flowers, peace signs and doodles.
"Friends know me from behind, before they even see my face, " she says. "That's a good thing, right?"