Talk about impact. When 15 VISTA volunteers in Madison, Wisc., discovered a huge gap in literacy between third grade African American and Caucasian children, they recruited and trained about 200 other volunteers to teach reading. Within a few years, they had closed the gap.

Those kind of stories were highlighted at a White House briefing on “Volunteerism in America.” Officials predict baby boomers will double the number of older American volunteers in coming decades. Many will be on their way to paid encore careers, after testing the water with unpaid volunteer gigs.

The White House event launched a new Web site, Volunteering in America, that provides detailed information about how and where Americans volunteer, research data on volunteerism, state and city trends and a search tool powered by USA Freedom Corps that identifies volunteer opportunities by zip code or state.

According to a new report, volunteerism is strong and poised for growth. Nearly 61 million Americans volunteered during 2007, with corporations expanding social responsibility programs, colleges adopting service learning, and political leaders from both parties embracing citizen service.

At the briefing, speakers stressed that volunteers do not constitute free labor: investment and management is needed to make effective use of their time and talent.

Speakers advised hiring skilled volunteer managers and coordinators, providing a “career ladder” for volunteers, showing volunteers the true impact that they are making on their community, and matching volunteer jobs with the volunteer’s skills. That is, don’t ask an accountant to file papers!.

The panel was moderated by David Eisner, CEO of the Corporation of National and Community Service. Panelists were John Bridgeland, president and CEO of Civic Enterprises; Joe Hale, who serves on the National Board of Trustees and National Leadership Council of the March of Dimes; Karen Kaskey, executive director of PennSERVE; and Stefanie Weiss, vice president for communications for Civic Ventures.