Childhood friends Billie Joe Armstrong (lead vocals and guitar) and Mike Dirnt (bass) are from Oakland (across the San Francisco Bay from San Francisco ) and formed a band called Sweet Children when they were just 14. Their first live show was on October 17, 1987 , at Rod's Hickory Pit in Vallejo, California . Drummer John Kiffmeyer joined the line-up in 1988 ; he was previously in Isocracy . By the time their first EP, 1,000 Hours came out on Lookout! Records in 1989 , they had dropped the name Sweet Children , since it was similar to that of another local band, Sweet Baby . Their new name, Green Day was selected because of their fondness for marijuana.