Like this movie a lot. Here are some sad facts about the actors. The film was released in 1955.
James Dean: James Byron Dean was killed in a car collision at age 24. That's the same age he was in the movie portraying a teenager. He died three weeks before the opening of Rebel Without a Cause. He made 77 movies and was credited in three of them; Rebel Without a Cause, Giant and East of Eden. BTW, those are all splendid movies.
Natalie Wood: Natalia Ni kolvaevna Zacharenko (Russian immigrant parents) drowned in the Pacific Ocean off Santa Catalina Island, California at the age of 43 (1981). This drowning may not have been an accident, and her body, when found, had a .14% blood alcohol level at the time of death and multiple bruises. She was 16 in Rebel Without a Cause. She played the part of a rebellious teenage named Judy and was nominated for an academy award.
Sal Mineo: Salvatore Mineo Jr. died in 1976 at age 37 after being stabbed in the chest by an unknown assailant outside his apartment. He was 17 years old in Rebel Without a Cause and was nominated for an academy award for his role as John "Plato" Crawford.
Does this seem at all strange to you?