Former first daughter Chelsea Clinton urged people to participate in service projects, saying there's a chain of service that links generations of Americans from all across the country.

Clinton is the daughter of former President Bill Clinton and Secretary of State Hillary Rodham Clinton. On Saturday she spoke at a summit on the National Mall for the National Day of Service.

Clinton said she was inspired by the volunteer work of her grandmother, Dorothy Rodham, who began as a child volunteer teaching migrant workers English and kept up her volunteer efforts for her entire life.

President Barack Obama, first lady Michelle Obama, Vice President Joe Biden and his wife, Jill, are participating in service projects throughout the Washington area.

Volunteers also are organizing service events in all 50 states.