Forget-Her-Nots by Amy Brecount White
When someone leaves three mystery flowers outside her dorm door, Laurel thinks that maybe the Avondale School isn't so awful after all -- until her own body starts to freak out. In the middle of her English presentation on the Victorian Language of Flowers, strange words pop into her head, and her body seems to tingle and hum. Impulsively, Laurel gives the love bouquet she made to demonstrate the language to her spinster English teacher. When that teacher unexpectedly and immediately finds romance, Laurel suspects that something -- something magical -- is up. With her new friend, Kate, she sets out to discover the origins and breadth of her powers by experimenting on herself and others. But she can't seem to find any living experts in the field of flower powers to guide her. And her bouquets don't always do her bidding, especially when it comes to her own crush, Justin. Rumors about Laurel and her flowers fly across campus, and she's soon besieged by requests from girls -- both friends and enemies -- who want their lives magically transformed -- just in time for prom.