Get ready for a media frenzied, Secret Service-ridden Monday in San Francisco. First Lady Michelle Obama is gracing us to promote volunteerism, and will be joined by California's First Lady Maria Shriver at Bret Harte Elementary School midday.  But fashionistas be warned, there will be no high heels or yellow dresses to dissect (well, we hope not) -- they're getting down and dirty and building a playground (along with the folks from KaBOOM!, who build playspaces for kids around the country).  It's all part of the United We Serve summer service kickoff, and there's a series of events across to motivate the masses to, well, do something. For volunteering ideas and inspiration, the Obamas urge us to check out Corporation for National and Community Service. So we should probably do that. In the meantime, be on the lookout for papparazi.