Seven years after one of the worst natural disasters in U.S. history, a group of Marin teens is heading back to New Orleans — just as it has every year for the past five years — to help rebuild homes.

ReNew Orleans, organized by St. Francis Episcopal Church of Novato and St. Raphael Church of San Rafael, has grown from seven teens in 2007 to more than 30 who will join in the effort July 7-14 to help families still coping with housing problems after Hurricane Katrina devastated the area in 2005.

Beth McMurphy, a St. Raphael youth coordinator who leads the trip to New Orleans, said the project simply grew out of the need for help in the years after Katrina. The church had done similar trips to Mexico and wanted to go where volunteers were needed most, she said.

"Teenagers don't feel like they have a big impact if they don't have lots of money or are a big face," McMurphy said. "That swinging a hammer makes a really big impact is an amazing thing to watch the kids understand."

Sara Haugen, a recent graduate of San Marin High School in Novato who has gone on every trip since its inception, said that although hard work has slowly rebuilt parts of New Orleans, there is a lot left to be done.

"There are still blocks that used to be houses that are just lawns," Haugen said.

Members raise money and pay their own way to New Orleans. Each member is required to raise $1,000 through donations from friends or family on top of other group fundraising efforts.

Collin Spencer, a 2009 Novato High School graduate now a senior at California State University at Monterey Bay, also has gone on every trip since 2007. He said he enjoys returning because he can see a family come full circle, from homeless to proud homeowner.

"The best part was coming back the next year and seeing the home finished and the joy on their faces," Spencer said. "You came again and they are so happy to see you didn't forget."

Members live in hostel-style housing while they are there. Each day is spent working on either houses or community centers that provide services to families who seven years later are still without homes or resources.

Haugen said it's especially satisfying to see how much residents appreciate the help on their homes.

"(One family) would make us lunch every day and they were so giving, even though they didn't have much to give and were still living in a FEMA trailer," Haugen said.

Haugen, who will attend Seattle University in the fall, said that besides the obvious benefits for New Orleans residents, there are also benefits for the Marin volunteers. She added that the volunteer work has helped influence her life goals, including her course load in college.

"Now that I have gone on mission trips, I decided to minor in nonprofit leadership," Haugen said. "In a sense, this has started me off on what I want to do."