Yvette Mimieux was 17 in Platinum High School when she played the character 'Lorinda Nibley'.
That was over 64 years ago in 1960.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
In 2022 she died aged 80, starring in 40 films in her career, 39 of those after Platinum High School was first released. If she were alive today she would be 82.
In Platinum High School, I think Yvette Mimieux looks: