I was nearly sure I knew this, so have just checked it and after all these years, I had remembered right! It was OLSEN. I also checked that this is the correct spelling, as there are some possible variations. (And Danny's surname was Zuko - it's all coming back...)
The real reason I remembered it was because at the time I thought it was Dee (remember Stockard Channing's song "Look at me, I'm Sandra Dee"?) Not knowing that this was the name of a well known actress, I assumed that the Sandy character's full name was Sandra Dee, and didn't discover my mistake for some time afterwards (while reading the book of the film, I think.)
In case you are interested in"Grease" trivia, there is a website here which seems to have all kinds of information on the movie.
The real reason I remembered it was because at the time I thought it was Dee (remember Stockard Channing's song "Look at me, I'm Sandra Dee"?) Not knowing that this was the name of a well known actress, I assumed that the Sandy character's full name was Sandra Dee, and didn't discover my mistake for some time afterwards (while reading the book of the film, I think.)
In case you are interested in"Grease" trivia, there is a website here which seems to have all kinds of information on the movie.
