Knowles made her first major acting appearance in 2005 when she played the recurring character Vanessa on season two of the hit Nickelodeon television show Unfabulous. She was later in the Disney Channel Original Movie, Jump In! as Shauna Keaton, alongside Corbin Bleu and Keke Palmer. In 2007, she played a small role in Super Sweet 16: The Movie. Her biggest and most well-known role to date, however, has come from her recurring role as Amber Addison, a snobby popular mean girl and frenemy/rival of main characters Miley Stewart and Lilly Truscott, on the mega-successful Disney Channel television show Hannah Montana, appearing in all four seasons of the show during its run from 2006 to 2011.
Despite numerous reports to the contrary and sharing the same last name, she has stated that she has no relation to singers Beyoncé Knowles and Solange Knowles.[5]