Dagmar Hedrich
IMDB says she was born in 1935. Which would make her 39 years old when this was filmed in 1974. She's portraying a girl at a boarding school, LOL! I'll admit, she doesn't really look 39, but she certainly didn't look to be 16 or any kind of teen, as she's supposed to be. The obvious and awful tit implants don't exactly go along with the young orphan schoolgirl she supposedly is.
Still this movie is amusing, just for how ridiculous it is. No actual terror or tension anywhere. The only thing horrific is the actual killing of a live snake at the end, which wasn't even done cleanly to be quick, unfortunately.