If your inner Boy or Girl Scout has been pounding on the door lately, hit Sierra Summit 2005, the Sierra Club's National Environmental Convention & Expo. But please, don't take the SUV -- these folks mean business when it comes to protecting our planetary resources. The expo is a great way to learn what's going on in the Earth-conscious business world as green companies from all over the country -- such as chlorine-free product makers, mobile-phone recyclers, and healthy-lifestyle book publishers -- gather to promote their wares, but there are also a number of interactive treats, like the Extreme Climbing Wall, where you can show off your skills, as well as a knot-tying clinic for those who never quite learned the ropes. Included in a one-day pass is admission to the Sierra Summit Film Festival, featuring intriguing flicks like Alone Across Australia, a documentary that follows Jon Muir and his dutiful pup on an arduous 128-day trek across the land Down Under. Outdoor hikes start at 8:30 a.m. Wednesday (and the exhibit hall opens at 10 a.m. Friday) at the Moscone Center, 747 Howard (at Third Street), S.F. Admission is free for the hikes, $15 for the expo, $75-385 for a full pass; call 974-4000 or visit www.sierrasummit2005.org.
-- Karen Macklin
Enjoy an outdoor opus
Michael Tilson Thomas -- you're curious about the man, huh? The music director for the San Francisco Symphony is the city's premier highbrow celebrity, especially among those who know nothing about classical music. His bio is filled with star turns conducting orchestras, and his New York debut is the stuff of legend: At age 24, he sprang to the stage midperformance when the Boston Symphony's William Steinberg fell ill. Now you can see him lead his brood in a manner that, under different circumstances, would be terrifying for performers of this caliber: They'll be sitting in a park, like well-dressed buskers, playing Tchaikovsky for a freeloading audience. The free outdoor concert starts at noon in Yerba Buena Gardens, Fourth & Mission streets, S.F. Call 543-1718 or visit www.yerbabuenagardens.com.
-- Michael Leaverton