Have you ever owned a tweener?

A tweener, dear Fool, is like your pal Chuck. Still a great athlete, Chuck no longer rules the hardwood with his 40-inch vertical leap. He's become what we sports addicts call a "gamer." He passes more. He's developed a nice shot from the corner. And, though he doesn't dunk as much, or as spectacularly, as he did, Chuck is still a force in the paint.

But we fans don't know how long Chuck will be in the starting line-up. Chiseled veteran Abe has a wicked hook shot that won't quit. And Larry, the little guard whose hip-shaking moves smoke defenders, has the makings of a future superstar. Both are vying to cut into Chuck's minutes on the floor.

In Foolish parlance: Chuck is a tweener, Abe is a Rule Maker, and Larry is a Rule Breaker.

Growing up is hard to do
The stock market has plenty of Chucks. They'll either create billion-dollar fortunes as they come to dominate industries, as Cisco, Microsoft, and Google have, or they'll be destroyed in the process, as Gateway was.

Therein lies the problem. Investing in tweeners can be dangerous -- and exceptionally profitable. The trick is picking your winners well, as David Gardner has. He produced nine years of 20% average returns hunting for misunderstood multibaggers in the making. His team at Motley Fool Rule Breakers continues the tradition today.

Let's have the list
You, too, can join in the effort, thanks to Motley Fool CAPS. Each week, we'll use the database to find three-star stocks that are expected to boost earnings by at least 15% annually over the next five years. Here is today's list:

Company

CAPS Rating

5-Year Growth Estimate

SunPower (NASDAQ:SPWR)

***

38.3%

DeVry (NYSE:DV)

***

19.1%

Knoll (NYSE:KNL)

***

19.8%

Ritchie Bros. Auctioneers (NYSE:RBA)

***

17.3%

EMCOR Group (NYSE:EME)

***

15.0%

Sources: Motley Fool CAPS, Yahoo! Finance.

Bear in mind that this isn't a list of recommendations. Instead, I offer these stocks as candidates for further research. But of these five, it's educational services specialist DeVry that interests me most.

Call it riding the lifelong learning trend. DeVry offers everything from professional training for adults transitioning into new careers, to online learning for high school students. The latter could be a major source of new growth. According to the U.S. Department of Education, enrollment in online high school programs grew by 73% annually from 2000 to 2006.

I'm also impressed by the wide array of All-Star Wall Street firms that have given DeVry the green thumbs-up.Bank of AmericaandCitigrouptop the list of white-shoe stock pickers, althoughJPMorgan Chasealso made a very profitable call in July.

Intrigued? Do your own due diligence, and then check in with tens of thousands of other investors at CAPS. Add your own commentary, if you'd like. You'll be helping your fellow Fools and testing your ideas at the same time. Click here to get started now; the service is 100% free. 

See you back here next week for five more growth stocks stuck in the middle.

How great is growth? More than 10 stocks in the market-beating Rule Breakers portfolio have at least doubled. Discover their identities with a 30-day guest pass to the service. There's no obligation to subscribe.

Microsoft is an Inside Value pick, while JPMorgan Chase and Bank of America are Income Investor picks.

Fool contributor Tim Beyers, ranked 10,724 out of more than 70,000 participants in CAPS, is a regular contributor to Fool.com and Rule Breakers. Tim didn't own shares in any of the companies mentioned in this article at the time of publication. Click here for Tim's portfolio and here for his latest blog commentary. The Motley Fool's disclosure policy prefers a little less conversation and a little more action.