Thinking about President Obama's recent speech calling on Americans to spend part of their summers devoted to community service and volunteering, I went looking for voluntourism opportunities. Starting with Sheryl Kayne, who is just out with "Volunteer Vacations Across America" (Countryman Press), I couldn't resist asking, "Why would anyone want to work during their vacation?"

"Actually," Kayne replied, "the only people who ask me that question are journalists, not the people I meet on the street. They want to set an example for themselves and others."

Ouch. Clearly, this column is traveling in the wrong circles. Kayne's book does a fine job of detailing more than 200 service/travel opportunities, including rescuing loggerhead turtles and learning to surf in North Carolina, and biking from coast to coast to raise money for low-income housing in the Bike & Build program (www.bikeandbuild.org).

"To have the president of our country ask us to give back at a grass-roots level is such a perfect match with the actual programs that are going on," said Maui resident Kirsten Whatley, author of "Preserving Paradise" (Island Heritage Publishing, 2008). "Most people know Hawai'i through hotels and lu'aus and water sports. Interacting with the people of Hawai'i gives you a completely different understanding of the deeper issues."

Whatley's book highlights more than 60 organizations on all the islands tourists typically visit. They "run the gamut of desires and strengths, and sometimes you don't have to give up any more of your vacation than four hours on a Saturday afternoon," she said.

Since it's Hawai'i, there are lots of beach-oriented volunteer opportunities, such as performing surveys of reef and other underwater life. ("You go in with a waterproof fish card and record the types of fish that you see, as well as the numbers.") For her part, Whatley is "more a mountain goat than a fish" and fondly recalled a Saturday last fall when she was one of 30 volunteers on the leeward side of Maui's spectacular Haleakala crater. In a single day, the group planted nearly 1,300 native trees and shrubs.

"It's as much about the people as it is the environment," Whatley said. "You start off as a group of strangers, but by the end of the day there is such a feeling of family and camaraderie."