Songfacts®:

• The song is Katy Perry's take on what happens when tomboys grow into young ladies with more feminine tastes. She called it a "coming-of-age type song," telling the New York radio station Z100: "Something happens from junior high to high school: We girls start blooming; guys start developing crushes. No longer are we playing dodge ball; we want to sit and paint our fingernails instead."
• "One Of The Boys" is the title track to the first Katy Perry album, although she released an album seven years earlier in 2001 under her real name, Katy Hudson. That was a gospel album where she conformed to her religious upbringing - her parents are both pastors and didn't let her listen to pop music. Rebranded as Katy Perry, she went hard in the other direction with her 2007 single "Ur So Gay." The first single from the One Of The Boys album was another song you won't hear in church: "I Kissed a Girl." That one was a #1 hit and launched her to stardom.
• Katy Perry wrote the song herself. She writes or co-writes her own songs for the most part, giving them a personal expression that is often energetic, rebellious or silly (sometimes all three). The song was produced by Butch Walker, whose other clients include Avril Lavigne, Pink and Weezer.
• Despite being the album's title track, the song wasn't released as a single and doesn't have much of a following. Perry performed it a fair about the few years after it was released, but as her discography grew and the hits mounted, "One Of The Boys" was pushed aside.