Flunk began as a project between Ulf, and Jo in Oslo, Norway in late 2000 and early 2001. Beginning as an instrumental and sampled vocal project, they were signed for a track on a compilation by Beatservice Records in winter of 2001. On hearing the finished track, label manager Vidar Hanssen signed the still-unnamed band for a full album. During early summer 2001, Ulf and Jo recorded most of the album and Anja improvised the vocals. After their vocals, Jo layered the guitars, but it would be a year before the album would be completed and released. In spring 2002, the band was known as Flunk and they released their first single, a cover of New Order's Blue Monday in April. The track was well received in the UK and was included on numerous compilations in North America and Europe. Later in April, their debut album For Sleepyheads Only was released which garnered great reviews in Norway. With the success of their album, BBC invited them to do a recording session for the Radio 1 show The Blue Room in London. Shortly after Notting Hill Art's Club would become the location of their live debut. In the United States, they signed with Guidance Recordings. By summer 2002, the band was getting rave reviews from British electronica magazines and in July they played Norway's finest rock festival. In October For Sleepyheads Only was released in the US through Guidance Recordings. In November they played the London Jazz Festival. Throughout 2003 their debut, For Sleepyheads Only was still being echoed across the globe in staggered releases with special editions released to Russia and Greece. Beatservice Records then went on to release Treat Me Like You Do - For Sleepyheads Only Remixed in June. While their debut continued to make its way around, the band wasted no time and began work on their second album for the majority of the year, which was recorded in Paris in October. Their second album, Morning Star was finished in March 2004 and saw a Norwegian release in May while it was released in the rest of the world in June. In 2005, Play America was released on Beatservice Records which included bonus tracks from the US version of Morning Star along with remixes. In 2007 Flunk released their next album, Personal Stereo, while May 2009 saw the release of This Is What You Get, which includes a cover version of Radiohead's Karma Police.
In January 2005, Flunk's track "Play" off Morning Star appeared on an episode of The O.C. called "The Risky Business" and later appeared on . In April 2008, the track appeared in Episode 5 of the PBS series "Carrier", during the swimming scene. The song "Spring To Kingdom Come" was featured in an episode of the television series Numb3rs. The song "See Thru You" was featured in the fourth episode of the television series Big Love, "Eclipse". The song "Blue Monday" can be heard in the movie, Walking Tall, starring The Rock. The song "Honey's In Love" is heard briefly in an episode of The L Word in 2005. The song "Blue Monday" can be heard in the movie "Nancy Drew" The song "On My Balcony" is featured in the new Timotei advert as of May, 2008 The songs "Morning Star" and "Six Seven Times" are currently being played in Victoria's Secret stores in the United States. The song "Personal Stereo" appears in a Norwegian commercial for the Volkswagen Tiguan 2011 model. The song "Only You" appears in an episode of the second season of the series "Designated_Survivor_"