Sweet Valley High is a book series created by Francine Pascal, who presided over a team of ghostwriters for the duration of the series' creation in 1983. The series ended twenty years later with over 152 books to its name. Over the years, the books were written by many ghostwriters (including Emmy-award winning screenwriter Rodney Vaccaro), and revolved around the lives of teenagers Jessica and Elizabeth Wakefield, twins who live in Sweet Valley, California. The series quickly gained popularity and spawned several spin-off series. The last Sweet Valley book, Sweet Valley University, was published in January 2003. The books are generally classified as young adult or kids' fiction.