BELFAST — Soon, an empty storefront in the Reny’s Plaza will see a whirlwind of activity as teenage girls search for the perfect prom dress — and then take it home for free.

The Cinderella Project of Maine, now in its sixth year, is bigger than ever, according to organizer Jessica Woods. Last year, the nonprofit gave 140 new and gently used dresses away to girls who needed one. This year, organizers are aiming to give an even larger number to young women from Waldo County, the Bangor area, Mount Desert Island and beyond this coming Saturday.

Dresses have been donated from fairy godmothers’ closets throughout Waldo County and also further afield, Woods said, with dress drop-off spots at Hannaford stores in Bangor, at Bangor Savings Bank locations around Waldo County and in Camden and Rockland, and at Belfast Area High School.

“We never want a girl to leave without a dress,” Woods said.

In exchange for the dresses, the girls are asked to “pay it forward,” by doing a good deed for someone else.

“It’s a recycling project. For years and years, probably generations, girls have swapped dresses,” Woods said. “We feel really good about being able to do the Cinderella Project, because it makes us feel great. We just try to remind them that they could pay it forward.”

Waldo Community Action Partners once again are sponsoring the project, and Reny’s is donating the display space in the plaza for the second year in a row, Woods said. And with prom season fast approaching, the interest in the Cinderella Project is growing, she said.

Last week, a group of girls from Belfast Area High School helped move 3,400 prom dresses in a couple of hours, as the former Waltz Pharmacy space filled up with racks of dresses in a rainbow of colors, and there’s “lots of chatter” on the group’s Facebook page, according to Woods.

Students at Unity College and St. Joseph’s College in Standish just completed dress drives, said organizer Mandie Sawyer of Belfast.

“It’s a big project,” Woods said.

Girls who attend the event can expect to find more than the array of prom dresses. Other items will include shoes and accessories such as jewelry, she said, and the project also will accept donated dresses during the event. Some of those may not make their debut until next year’s Cinderella Project if they need cleaning or other TLC.

Organizers are always looking for plus-sized dresses, Woods said, with a full rack this year of sizes 16 and up.

“We just love the Cinderella Project, and we’re very proud of it, and we want it to keep going,” she said.

The 2011 Cinderella Project dress giveaway will be held from 8 a.m. to 2 p.m. on Saturday, April 9, in the former Waltz Pharmacy in the Reny’s Plaza in Belfast. There is no cost for any of the dresses, jewelry or accessories. Dressing rooms will be available to try on gowns and BAHS and other community volunteers will be on hand to assist with the selection process.

For more information, call Jessica Woods at 338-1790, ext. 310, Tabitha Lowe at Waldo Community Action Partners, 338-6809, or email Donations are tax-deductible.