:Bubblegum pop does NOT refer to the Backstreet Boys or N'Synccheck the link if you doubt that. Bubblegum pop is the teen stuff from the late 60s and early-mid 70s. I don't know that I would exactly call it a sub-genre of power pop, but it's certainly a related genre. "Goody Goody Gumdrops" by the 1910 Fruitgum Company, "Love Grows" by Edison Lighthouse, "Fox On The Run" by Sweet and just about all of the hits by the Bay City Rollers would be considered classics of both bubblegum pop and power pop.