Supergirl Mixtapes is a quick and engaging read for older teen girls. Main character Maria has an extremely irresponsible, selfish, neglectful, and immature mother. Until Maria goes to live with her mother though, she really has no idea what her mother is like. Her mother left her, years prior, when her parents divorced, and her responsible, if stoic, father has done his best to raise Maria. Subject matter is heavy, as drug addiction, dysfunctional parenting, and attempted suicide are all central to the story. Smoking, both cigarettes and pot, takes place, teens drink alcohol, sex is referenced, and characters are subjected to some rather serious bullying. Language is graphic and quite prevalent. A few characters are openly gay and one is referred to using derogatory slurs. At its heart, this is a story about a girl whose eyes are opened for the first time to her mother's true character, and her relationship with her father is finally appreciated and respected. Music is an important element, and many musicians, bands, and songs are mentioned, which may pique the interest of music lovers.