Teens are shopping—just not at the full-price mall

Retailers may be holding their collective breath, hoping the shoppers will show uop soon.

This weekend is traditionally a big one for back-to-school shopping, but summer sales haven't inspired confidence that retail's second-most important season will be strong.

American Eagle Outfitters and Aéropostale both warned investors about slower-than-expected sales and lower earnings expectations.

A combination of factors are crimping sales for apparel retailers. High unemployment, elevated gas prices and increased payroll taxes are still pressuring consumers, but there are retailer-specific issues as well.

Teenagers may simply have lost interest in what Aéropostale and American Eagle are offering, said KeyBanc analyst Ed Yruma.

"What we are seeing is that teens are spending more for some of these 'need to have' accessories," Yruma said. "Whether it be the Michael Kors' handbag [or] the North Face backpack, what they're doing is mixing and matching that with less expensive items. ... So really giving it a high-end plus a fast-fashion-type look.

That approach makes it tougher for traditional youth retailers such as Abercrombie & Fitch, Aéropostale and American Eagle as the pricier players soak up significant chunks of back-to-school dollars.

(Read more: Huge deals on back-to-school clothes)

At a recent Piper Jaffray Consumer Conference, a panel of high school students told attendees that they planned to apply some of their back-to-school budgets to a Coach handbag, a Louis Vuitton iPad case or a Kate Spade wallet. In a survey of thousands of teens, Piper Jaffray found Michael Kors followed Coach on the coveted-handbag list, while Vera Bradley came up third.

While Coach, Kate Spade and Michael Kors merchandise is sold in department store such as Macy's (in addition to dedicated boutiques), teens and their families have been flocking to outlet malls in search of designer duds.

Traditional mall traffic may be weak this summer, but outlet malls appear to be faring better. At Simon Property's Woodbury Common in Central Valley, N.Y., young adult shoppers patiently stood in lines outside Michael Kors, Tory Burch, Kate Spade and other designer stores.

(Read more: Busting the myth of back-to-school tax holidays)

"I've been to Under Armour, North Face, Michael Kors—probably going to Coach and Nike," said Gabrielle Perry, a 16-year-old from New Jersey. "Michael Kors has bags for 50 percent, and they are nice bags, too."

Claire Muldren, 20, is also a Kors fan. She left the store with a new iPhone 5 case, and her friend is hunting for a high-end wallet "for school and going out."

High-end department stores don't want to miss out on the outlet boom. Saks and Nordstrom both have more outlet than full-line locations. Last month, the latter announced that four new Nordstrom Rack stores were in the works.