Sweet Valley Kids were when they were kids, Sweet Valley Twins (and friends) they were in middle school. There was a spinoff of that with Jessica and the Unicorn Club. SVH which covers the first two years and then there was the SVH: Senior Year. Which then leads into SVU, which is the first 2 years of University, then there was the Elizabeth series, which she leaves for London. Then there was the dreaded Sweet Valley Confidential, which is 10 years later, which is written by the author.