The album topped the South Korean Albums Chart (MIAK). It was certified platinum by Music Industry Association of Korea (MIAK). It producedfive singles, "Irony", "Bad Boy", "It's Not Love", "Tell Me" and "This Fool". Also, a music video for a soul track "Wishing on a Star" was released, however it wasn't released as single. Singles "Irony" and "Tell Me" topped various musical charts. Although member Hyuna left two months before album was released and was replaced by Yubin, all tracks on album featured Hyuna's vocals. Only the rap version of "Tell Me" features Yubin's raps. Also, Yubin sings on track "Wishing on a Star". The Wonder Years was a sequel to Wonder Girls' extended play (EP) The Wonder Begins (2007) and a prequel to Wonder Girls' second extended play The Wonder Years: Trilogy (2008). On April 23, 2012, album was re-released through recording label KMP Holdings.

Wonder Girls were formed in 2006 by Park Jin-young during the television reality show MTV Wonder Girls (2006–2010), during which they held their first performances, rehearsals and recording sessions. At first a quartet, the fifth member Park Yeeun, also known as Yenny, joined the group and the group released their successful debut single "Irony" in February 2007. The same month, their debut extended play The Wonder Begins was released and was followed with two more singles "Bad Boy" and "It's Not Love". Latter was used as the soundtrack for film Hellcats, in which member Sohee starred. In July 2007, group's rapper Hyuna left the group due to health problems and was on hiatus until she joined another South Korean girl group 4minute. She was replaced by rapper Yubin who was originally a member of girl group Five Girls but joined JYP Entertainment when the group disbanded. Their single "Tell Me" was released in September 2007 and became one of their biggest hits. The remix, titled "Tell Me (Rap Version)" was made to include Yubin's vocals and was included on their 2008 EP So Hot. The album was recorded in Seoul from December 2006 (when MTV Wonder Girls first aired) until 2007. The title of the album is The Wonder Years, however on album cover and Discogs it's titled The Wonder Years (The First Album) while on HanBooks it's titled The Wonder Years (1st Album). Also, album cover features a colorful background behind all five members (Yeeun, Yubin, Sohee, Sunye and Sunmi), who are jumping.

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