SAN FRANCISCO (AP) — First lady Michelle Obama has joined administration officials promoting the value of volunteering.

The initiative, called United We Serve, was launched last week by President Barack Obama in a video message. He’s urging people to help in the nation’s economic recovery by volunteering at schools and hospitals and by pitching in on community projects.

Michelle Obama joined California first lady Maria Shriver and several hundred local volunteers at an elementary school in San Francisco. The school is transforming part of its playground into a garden and produce stand that will be staffed by kids and seniors. Proceeds will go to the school.

Monday evening Mrs. Obama told the 2009 National Conference on Volunteering and Service that volunteering isn’t easy, even in good times. She said meeting community challenges and achieving “real change” will come from “the bottom up.”

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