Continuity mistake: When the Drapes are singing to Allison/Baldwin/Mrs. Vernon Williams, the song, "Gee, I Love that Girl" in the speeding cars, Hatchet-Face's gold earrings are on, then off, then on again. They are seen again in other scenes.
Other mistake: When Cry-Baby's gang arrives and Uncle Belvedere is taking a bath, Snare-Drum and Suzie Q ask Hatchet to make the monster face and Snare-Drum starts to run, but then he appears on the other side of Suzie Q and runs after her.
Continuity mistake: In the very beginning of the film when all the kids are leaving school and Lenora is standing on the steps watching Allison talk to the drapes at first her hair barrette in on one side of her head and the camera goes to Cry-Baby and Allison. When the camera switches back to Lenora her hair barrette has somehow moved to the other side of her head.
Continuity mistake: When Cry-Baby (Johnny Depp) sings, "Doing time for being young," he rips his shirt wide open, but in the next shot the shirt's only half open, then in the following shots it's completely open again.
Visible crew/equipment: When Cry Baby is riding Allison to Turkey Point for the first time, you can see a white balloon with a flashing light in the right hand side for at least thirty seconds.
Factual error: In the time Cry Baby is based, there was racial tension (the judge even makes a racist remark). The jails would have been segregated until 1965, yet when Cry Baby goes to jail, both white and black people are in the scene. That would only ever happen during rec time and meals.
Factual error: At about the 5 minute mark, cry-baby reaches into his ride and turns on the radio, which is immediately audible. However, in 1954, all car radios were tube-type, which required a warm-up period.
Continuity mistake: Early in the movie, when the Drapes are chasing and then pass Mrs. Vernon Williams' car, they repeatedly drive past the same trees on the roadside, about six times.
Factual error: When Cry Baby is getting his tear drop tattoo in the hole, the guy calls him "home boy." Cry Baby is set in the fifties-early sixties."Home Boy" didn't come into use until the very late sixties early seventies, and still was not popular until the early eighties.