Record Store Day 2012: Iggy Pop is the ambassador of this year's nationwide Record Store Day happening on Saturday, featuring a special Iggy And The Stooges Record Store Day release, plus many more special releases, deals, and festivities in participating stores.

World Naked Bike Ride: Get out that anti-chafing cream, it's that time of year when folks ride bikes in their birthdays suits. Quite often these naked riders are ones you'd rather not see naked.

Annual Cesar E. Chavez Holiday Festival: The largest event in Northern California honoring the life and work of the beloved labor leader will take place on Saturday with a parade and festival featuring live music, entertainment and more.

Cherry Blossom Festival: The second weekend of the cherry blossom extravaganza happens this weekend with the big parade on Sunday and the festival all weekend with food booths, cultural performances, karate, live bands, Japanese sword demos, tea ceremonies, taiko drumming, origami demonstrations and more.

Earth Day: This year's Earth Day Festival at Civic Center brings green/sustainability leaders in an effort "to educate and activate the public" to save the world from itself. Meanwhile, at Crissy Field, the Earth Day Stroll will feature a diverse range of activities, from tortilla making, to nature sculpture, to live animal demonstrations from WildCare, to musicians on bicycles, as well as a new obstacle course adventure, the Park Pursuit.