Janet Smalley, the actress who played Putter's mother, slapped Yeardley Smith for real. Smith remarks on the DVD commentary that her face was numb after that particular scene was shot.
Yeardley Smith refused to cut her hair for the part. So when Putter cuts her hair, she is wearing a wig. When Putter first appears with her hair cut, the upturned collar on her jacket is to hide the real ponytail tucked in there.
Due to language, the film originally garnered an "R" rating from the MPAA. It was reduced to "PG-13" on appeal.
Playing a teenager, Martha Gehman (Ophelia) was already 30 years old when she filmed this, as she was born in 1955!Yeardley Smith herself was twenty years old when she was cast as the fourteen-year-old Putter, and her breasts had to be strapped down with an Ace bandage to make her look younger.
Christian Slater stated in an interview that while filming this movie he thought he was fated to marry Helen Slater because their last names were the same.