Lively was cast in The CW's series "Gossip Girl", based on the novel series of the same name by Cecily von Ziegesar, which premiered in September 2007. Already having deferred college for a year, Lively intended to turn the role down and become a student, but was told that she could attend college part-time while filming the show (she later said "This is advice to anyone: when they say, 'We promise, but we can't put it in writing,' there's a reason they can't put it in writing"). She played the role of Serena van der Woodsen in the teen drama until 2012 when the show ended. Her first magazine cover was the November 2007 issue of "Cosmo Girl", where she discussed her time in high school and her career prior to "Gossip Girl".