Green took to music at a young age, as he "began with the ukulele at three, the guitar at five, and the piano at seven." His talents were noted by a major newspaper when he was eight, following a performance of Arthur Laurents' "The Time of the Cuckoo". A local review by the "Los Angeles Times" wrote that "roguish-looking, eight-year-old Keith Green gave a winning portrayal" of "the little Italian street urchin, Mauro"; another review commented that he "stole the show". The show was Green's first appearance in live theater, which was held in Chatsworth, California in September 1962. According to the "LA Times", he had already done a number of television commercials and made a TV pilot.