They could have been just a novelty act, but the sheer energetic power of Gary, Indiana's Jackson brothers turned the youngsters into international superstars. Discovered at one of the Apollo's legendary amateur nights, the Jackson 5 found instant success with their 1969 debut "I Want You Back," featuring 11-year-old Michael's powerhouse lead vocal. A string of classic hits moved from bubblegum soul into a slick disco sound over the course of the '70s, but Michael's increasing solo stardom led to the group's demise following an enormous 1984 world tour.