Sugar Rush by Julie Burchill

Fifteen-year-old Kim is horrified when her dad tells her she's got to leave her posh private school and go to infamous Ravendene Comprehensive, 'the source and inspiration of five thousand urban myths and horror stories'. How will she survive in this wild and hormonal adolescent jungle? But then Kim meets gorgeous Maria (better known as Sugar) Sweet, queen of the 'Ravers', and falls instantly under her spell. Leaving her restrained, good-girl past far behind, Kim finds herself not only drawn into Sugar's exciting and daring life - but also asking herself a disturbing question: has she fallen deeply in love with her best friend?