Before it opened, people wondered whether the Minneapolis Central Library's space for teens -- Teen Central -- would sit empty.

"That was the question. Is it going to get used?" said Christy Mulligan, teen services librarian. She glanced around the room: teens working at each computer, sitting in each chair, talking at each table.

"We learned very quickly that not only is it getting used, it's not big enough."

Hennepin County also learned its lesson. The remodeled and expanded Brookdale Library in Brooklyn Center, which reopened in 2004, boasted its own teens-only area.

But within months it became clear it just wasn't big enough. "The teens responded so well that space became a problem," said Molly Schaaf, one of the library's managers.

They've since remodeled the remodeling, and the teen area doubled in size.

Hennepin County Library's new buildings -- Maple Grove and Plymouth are set to open in 2010 -- give teens plenty of room.

"The way we're dividing up the space is radically different," said Amy Ryan, director of the Hennepin County Library system. Adults get 40 percent of the area open to the public; children and teens split 60 percent. Plans aren't finalized, but in Maple Grove's 40,000-square-foot building, teens will likely claim 8,000 square feet. That's four times the size of Teen Central.

Libraries across the United States have, in recent years, focused on getting teens into libraries. Those that have succeeded give a few reasons for that:

• Give teens their own space.

• Create programming and activities for that space.

• Put teens in charge of both.

Teens helped give the Minnetonka Library's teen room a makeover: The small room that once resembled a conference room is now more like a lounge.

Teen Central, too, was designed by teens. About 175 of them gave input, often directly to architects, about what they did and didn't want. The result is a space separated not only by a door, but a catwalk, from the rest of the library and a freer area where food and drinks are not only allowed, but sold.

The teens hanging out in the back of the room one afternoon go there often. They joke about breaking in on Mondays, when the library's closed.

Keith Senart, a junior at South High School, goes to the library to talk with kids from other schools. "I'm a people person," he said. "And they've got nice people here."

Next to him, Ashley Grummons was listening to music on one of six laptops that teens can check out and use in the area. She said she's quiet at home and quieter at school, but here she's downright loud.

"We make her feel comfortable," Senart said. "Or uncomfortable -- whichever is more fun at the time."