Phoenix ? Since she was 5, Patti Duncan has faithfully attended weekly Girl Scout meetings, earned badges for taking care of pets and writing to soldiers, and sold lots of those famous cookies.

But each year, fewer and fewer of the 14-year-old’s fellow troop members returned. This year, Patti and her mom couldn’t even find four other girls in their large suburban neighborhood to form a troop.

“They didn’t want to do the badge work and just wanted to hang out with their friends,” Patti said.

The Girl Scouts have an image problem with older girls. It seems the 91-year-old organization — known for service, leadership development and, of course, Thin Mints — becomes uncool with the 11-and-older crowd. Of the Scouts’ 2.8 million members ages 5 to 17, 88 percent are younger than 11.

That number made it clear to Girl Scout officials that they needed to offer something different to attract — and retain — teens like Patti and “tweens” or preteens. After much research, a new program called Studio 2B was launched earlier this year.

“Everything was tested with girls,” said Harriet Mosatche, senior director of research and program. “It is very much a ‘by girls, for girls’ approach.”

Studio 2B doesn’t have girls wearing uniforms, earning badges or going to weekly meetings. Instead, girls plan what they want to do when they want to do it, with advice from a college student or young adult. They can earn “rewards” if they want.

Patti said she preferred traditional scouting but is interested in Studio 2B. The idea of having more control over what the group does, even down to the details of putting on an event, appeals to her.

Patti Duncan, 14, and her mom, troop leader Elaine Duncan, right, work on a Girl Scouts project at their home in Phoenix. Patti Duncan is a rarity in that 12 percent of Girl Scouts are over age 11. The organization is seeking a hipper image to keep tweens and teens actively involved.

“You plan something that you want to do,” she said. “You think it over and decide whether it’s a good idea or not.”

The Studio 2B’s Web site makes no direct reference to Girl Scouts. Its content is the stuff found in teen magazines: advice columns, polls, guides to good skin care and planning for the future.

The optional “rewards” are silver bracelet charms. A mirror, for example, represents the topic of body image; a money bag symbolizes money management.

“We’re not taking anything away from anyone. We’re providing more options,” Mosatche said of Studio 2B. “We know that what we have to offer is important for girls that either have never been in Girl Scouts or have dropped out.”

The Cactus-Pine Council in Arizona held pilot Studio 2B events, including an aerobics night and a mall scavenger hunt. The launch event was a night at swank salon where the girls learned about nail, skin and hair care.

“This is what they’re already interested in,” said Margaret Spicer, project manager of girl programming for the Cactus-Pine Council. The girls were so attentive in the salon, “you could have heard a pin drop.”