Greg Leffler, a site reliability engineer at LinkedIn, works outside his company's Mountain View, Calif., headquarters on May 7. © Noah Berger, AP Photo

 Kaitlin Rodriguez created a LinkedIn profile as a college junior and got serious about using the business-first social network in the last half of her senior year.

A communications major at the University of California Santa Barbara, Rodriguez used her LinkedIn profile as a digital resume while looking for entry-level public relations jobs. When she found openings at PR agencies, she logged on to the site to find anything that could get her in the door. "I'd see who worked there and where they went to school. I did some LinkedIn stalking," she says.

Rodriguez is the type of young job seeker LinkedIn hopes to reel in with recently introduced features and updated terms of service aimed squarely at college and high school students.

Last month LinkedIn unveiled university pages, which educational institutions can create to promote themselves to current students, potential students and alumni in the same way businesses use the network's company pages to share information about products and advertise job opportunities.

Under the new terms of service, students as young as 13 abroad and 14 in the United States can create an account and set up a profile. Formerly students had to wait until they were 18.

At first glance, going after younger users seems like an ill-fated strategy at a time when tweens and teens are skipping out on big social networks such as Facebook in favor of more photo-heavy, mobile friendly services such as Instagram, which Facebook bought last year for about $1 billion.

LinkedIn isn't known for projecting a youthful image. In a May 2012 study of teen Internet use by the Pew Internet Project, the network did not appear on a list of the dozen most popular hangouts for 13- to 17-year-olds.

But college students and recent graduates are the fastest-growing demographic group of the site, accounting for about 30 million of its 238 million users, according to the company. That is less than 13% of the total, but the number of students joining doubled in the 2011-12 school year. "There's a large opportunity," says Crystal Braswell, a company spokeswoman.

LinkedIn launched university pages with profiles of 200 schools around the world, including Arizona State, Notre Dame, Akron, Brigham Young and Denmark's Aarhus Universitet, and is adding more on a regular basis, Braswell says.

The University of Michigan page, for example, lists facts about the school, notable alumni and blog post-style updates provided by the school. LinkedIn members can see where 191,362 Michigan alumni on the network work and what they do, as well as their own connections who attended the school.

LinkedIn expects college students to use the new pages to find out about jobs, network with alumni and research graduate schools. By lowering the minimum age, the company also hopes to encourage high school students to use the service as part of the college search process.

By adding students and young graduates to its ranks, LinkedIn could make itself even more attractive to companies that pay thousands of dollars to license its corporate recruiting software, which in recent years has accounted for the majority of its revenue.

LinkedIn also is taking on rivals including Facebook, which features pages from more than 1,000 colleges.

and Twitter, which has accounts from more than 2,000 schools. Pinterest also is loaded with college- related pins and boards.

It remains to be seen whether LinkedIn's straight-and-narrow approach will succeed with the student set.

Rodriguez, 24, who lives in Culver City, Calif., used LinkedIn most while she was job hunting, but these days spends more time on Twitter and other networks.

During her initial post-graduation job hunt, LinkedIn helped Rodriguez get an interview, but the job she ultimately landed at a digital ad agency came from answering a Craigslist ad. When she started looking again, she jumped back on LinkedIn. "It was almost exclusively making connections to people I went to school with" and looking at open positions listed in the network's jobs section, she says.

In the end, Rodriguez didn't find her current job doing marketing for a Los Angeles bike maker through LinkedIn, although she did use the site to learn more about the business. Still, she thinks it was a smart move to start using it as early as she did. "I wanted to get ahead of the game, so I wasn't just starting after I graduated," she says.

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