MUSIC: SF's Girls, who are said by the New York Times to have an "Elvis Costello, Buddy Holly, and The Beach Boys" sort of vibe take the stage with SF's Sonny and the Sunsets performing "doo-wop laden, beach-ready tunes." Also featuring guest Carletta Sue Kay. (8 p.m., Great American Music Hall, 859 O'Farrell Street)

THEATER: Custom Made Theatre Company's production of The Underpants, a "hilarious, laugh-out-loud farce" based on Steve Martin's adaptation of the naughty, popular 1910 farce by German writer Carl Sternheim, Die Hose, has been extended to October 30th. (7 p.m., Gough Street Playhouse, 1620 Gough Street)

FILM: The new documentary American Teacher, chronicles the stories of four teachers in different areas of the country, revealing "the frustrating realities of today’s educators, the difficulty of attracting talented new teachers and why so many of our best teachers choose to leave the profession altogether." (4:45, 6:30, 9:45 p.m., Roxie Theater, 3117 16th Street)