Things to do this weekend in San Francisco

• North Beach: Art crawl.
• Oakland: Festival featuring local businesses, artists and performers.
• San Jose: Art walk plus music.

Take a polar plunge in support of Special Olympics Northern California.

• 5K, 10K and polar plunge tomorrow at Aquatic Park in SF, starting at 8:30am.

Take home some tulips at Union Square in celebration of American Tulip Day tomorrow from 1 to 4:30pm.

Listen to some reggae in Golden Gate Park as part of Illuminate Live's free outdoor concert series. Sunday from 4:30 to 7:30pm.