Teen Witch Books.
I really didn't know about this movie until I saw someone tweet about a song in the film. So my original take on this, was a question about some books I read as a teen in 1988. Does this movie have anything to do with the books? And the answer is NO. Teen Witch series by Megan Barnes introduced a character name Sarah.
If you're a fan of this type of story.... maybe these books would be a good read!
I did have some trouble finding them, luckily I knew they were from a publisher Scholastic. Which now you can find on Amazon or other stores. There are 4 books in the series as I know of. http://www.amazon.com/Lucky-13-Teenwitch-No-1/dp/0590412965