Trivia: Betsy Palmer was chosen to play Jason's mother strictly for the fact that she could provide her own transport to the set.
Trivia: In the scene where Alice finds Bill's body hanging on the back of the door to the generator room, the producers purposely did not tell Adrianne King what they were going to do to the body nor did they let her see the body beforehand. When she saw the body during filming it was for the first time. The scream she produced was genuine as it scared her badly. Needless to say, that entire scene was shot in one take.
Trivia: The original "Friday the 13th" was the most successful installment in the series grossing over $37 million. The whole entire series has grossed in excess of $250 million.
Trivia: The music in this film and all other Jason movies where its sounds like "kkkkk" and fades is actually supposed to be Jason saying to his mother "kill mom".
Trivia: Betsy Palmer took the role of Jason's mother in Friday the 13th because it paid what she needed to get a new car she was interested in.