Investing in teen-retail stocks can be as unpredictable as your teens' mood swings, with teen trends ranging from high-end Tiffany (NYSE: TIF) chains to daily coffee runs to Starbucks. Even though teen tastes can be as fickle as someone's BFF status (that's "best friend forever," for you nontexters), one thing was thought to be sure: Teen retail succeeds even in a recession.

But new trends show that teens are going frugal, shopping at thrift stores, and cutting back on spending in general. Not only are they getting less money from their parents, but they're also earning less money, since teen hiring has dropped by 5% since March 2007. Some are saying this could be the worst teen retail slump in 17 years, with high gas and food prices finally triggering teens to go retro and look for sales.

Are teens really buckling down?
There are initial signs that teen retailers are feeling the same pain that has trickled throughout the retail sector. March brought a 5.9% same-store-sales decline for teen retailers. Buckle (NYSE: BKE) was the big winner for the month, with a 20.9% same-store-sales jump, and Aeropostale (NYSE: ARO) experienced a 2.5% increase, but American Eagle Outfitters (NYSE: AEO) slashed first-quarter earnings estimates on a 12% same-store-sales drop in March, while Abercrombie & Fitch (NYSE: ANF) reported a 10% same-store-sales decrease, and at Pacific Sunwear (Nasdaq: PSUN), same-store sales fell by 8%.

Of these retailers, Aeropostale is typically the lower-cost option for teens. A quick look at the Aeropostale website shows teens wearing trendy styles and advertises a "2 for $20" sale on summer tops. American Eagle's website boasts sales for summer tops, too, but prices start at $15.50 for ladies' tops. Abercrombie is usually the most expensive brand and advertises only for future model searches on its website. No mention of sales here.

Buckle is the real surprise from the cost standpoint, with jeans prices starting at $70 and going into the $100s. Even a jeans sale brings the price down to $40 or $50 -- certainly not prices for the cost-conscious teen.

No in-between option?
What's most interesting in last month's teen-retail results is that the "bookend" shops at either end of the spectrum did the best, with high-end Buckle and low-end Aeropostale beating the mid-range stores. This definitely makes sense when you consider the economic environment: Teens from high-income families can continue to buy higher-end items, while middle-income teens trade down for their old standbys (American Eagle, Hollister, Abercrombie, and so on) for lower-priced options at Aeropostale.

This may spell long-term trouble for the "middle-class" retail stocks. According to a 2007 article from the Wharton School of Business, 11% fewer teens were working in 2006 than in 1989. Why? Typical teen jobs, such as newspaper carriers and grocery store clerks, are now going to baby boomers and other adults. Of course, some say that teens today are just lazier, or maybe Mom and Dad are footing more of the bills and teens just don't have to work. Whatever the case, if the economy continues to falter and more teen jobs are lost, there will be less money to go around, and the ripple effect will potentially hit teen retail.

Retailers are blaming a dull March on factors including lower-than-average temperatures and an early Easter. We have yet to see whether teen retail can pick it up in the summer, when the summer break allots more time for teens to shop and summer jobs create a steadier stream of cash flow, or whether teen retail will get hit by the recession, just the way everyone else seems to be.

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