Programs to lure youngsters into the parks. "Healthy Kids/Healthy Parks." Research to gauge the impact of visitation on park natural resources. Restoration work. These are just some of the projects that your taxable donations enabled to occur across the National Park System in 2008.

With a staggering $8 billion+ maintenance backlog, a centennial campaign struggling to gain momentum, and relatively flat budgets, there's no way the National Park Service can meet all its needs across its 84-million-acre landscape. That's where friends groups and foundations step in to provide as much sweat and financial aid as they can to not just help hold the park system together but to invigorate it.

These groups draw volunteers into the parks to perform trail projects and cleanups, provide dollars to underwrite both research and educational outreach, and bring attention to the parks' needs. While the groups view their role as providing a "margin of excellence" for national parks, more and more they're being relied on to help the parks simply cover the bases.

"More and more of the 20 million visitors to the Blue Ridge Parkway have sought out the Blue Ridge Parkway Foundation to make an investment in the park's future with their gifts," says Dr. Houck Medford, the foundation's executive director. "The Parkway's future remains questionable with one out of four current positions being vacant and, within another four years, 49 percent of the existing workforce being eligible for retirement."

While the foundation does not providing funding for operational maintenance or seasonal staffing that it views as an obligation of the Congress, it nevertheless takes on projects such as renovating boardwalks, combating non-native vegetation, and providing cameras for resource management and protection.

When it comes to providing that margin of excellence, though, the foundation has a solid record, particularly when it comes to getting younger generations wired into the park system. It landed a $200,000 grant from the Blue Cross/Blue Shield Foundation of North Carolina to initiate a "Healthy Kids/Healthy Parks" program in the parkway that works to combat childhood obesity, and underwrites the "Parks as Classrooms" program that brings rangers into classrooms to educate youngsters on the parks.

In Maine, the Friends of Acadia used some of its 2008 donations to "defend the Schoodic Peninsula from inappropriate development, worked with partners -- and within the organization -- on legislation and strategic planning to prepare Acadia National Park and the National Park Service for their centennial anniversaries in 2016, and launched the new Acadia Quest program, a program to encourage young people to explore and protect the great outdoors," says Lisa Horsch, director of development and donor relations for the friends group.

Down in Texas, Friends of Big Bend National Park doesn't yet have quite the financial clout of groups such as Friends of Acadia, the Yellowstone Park Foundation, or the Yosemite Fund, yet it still has managed to provide more than $750,000 to the park over the past dozen years.

"In 2008 Friends of Big Bend National Park provided over $100,000 to Big Bend for a variety of projects through license plate income, foundation grants, and individual gifts," says Courtney Lyons-Garcia, the group's executive director. "These range from wetland restoration in the Rio Grand Village area to the Teacher Ranger Teach Program to assistance for the park's preschool. Each project we provided funding for makes a difference to both visitors and staff."

In Montana, the Glacier National Park Foundation funds interpretive programs for Glacier National Park, underwrites an education specialist who works with school groups, pays for wildlife and vegetation research to ensure visitor use isn't overwhelming the park's natural resources, and rehabilitates both trails and historic buildings.

There are no shortage of projects for these and other friends groups to tackle. In 2009 the Friends of Big Bend will work toward a $150,000 goal to underwrite an orientation film for the park. At Acadia, the friends group expects to grant more than $1 million for park and community conservation projects and programs. In Glacier, the friends group hopes to raise another $20,000 for restoration of a 1913 ranger cabin, provide $40,000 for a "grizzly bear tree rub program" that helps scientists determine whether global warming is impacting the bruins, and begin a centennial campaign goal of inventorying the park's flora and fauna.

But with the nation's ailing economy, attracting donations for these projects is decidedly tougher this year than it has been in recent years.

"We have been getting lots of donations, but they are much smaller than last year," says Jane Ratzlaff, executive director of the the Glacier National Park Fund. "People still love us and want to support, but the economy has made it tougher, so we get notes like, 'Wish it was more, but just cannot this year.'

"We feel fortunate though, as people are still supporting us and notes like that make my day as I know they really care," says Ms. Ratzlaff.

At the Blue Ridge Parkway Foundation, Dr. Houck expects year-end giving to be down by 30 percent. Still, his foundation is better off than most, as it is going forward with a "2009 annual budget well over $1 million," he says.

At Friends of Big Bend, things aren't dire. Yet.

"Donations are definitely not up, but we have not seen a sharp decline, yet," says Ms. Lyons-Garcia. "I think we will be fine through the end of the year. It is March-May of next year that I am worried we will start to see the slowdown. I think most folks will renew their membership, but the extra gifts that people give here and there throughout the year will probably be where we see a drop."

Another group whose activities are controlled, in part, by donations is the Coalition of National Park Service Retirees, a watchdog organization that keeps tabs on NPS activities across the system and, along with representatives from the National Parks Conservation Association (yet another group that is driven, in part, by donations), testifies before Congress on park-related issues.

With a change in administrations around the corner, and deep concerns of how the outgoing Bush administration managed the parks, the coalition expects to be pretty busy in the coming year.

"CNPSR will continue to monitor and engage in issues that affect the purpose and values of the National Park System. Moreover, we will take appropriate opportunities to assist a new NPS Director and Secretary of the Interior in carrying out the mission of the National Park Service," says Bill Wade, the group's president. "CNPSR operates on several foundation grants but relies heavily on member and non-member donations. More information about the Coalition, its efforts and how to donate can be found on the CNPSR website.

These are just some of the groups that could use a lift when you make out your year-end tax-deductible contributions. You can help them out by buying a membership in their organization, purchasing a parks license plate for your rig if they're offered in your state, or simply writing a check.

To find more organizations that could use some help, head to the website of your favorite national park or Google your park with "friends group" and see what turns up. If all else fails, think of contributing to the National Park Foundation, which works to send assistance to all units of the National Park System.