Switchers

Tess has a secret that keeps her apart from others: she can change into an animal at will. Disturbed when scruffy Kevin keeps following her after school, Tess wonders what he wants from her, and why an arctic front is sweeping over the globe, causing a blizzard in Dublin in September. Then she learns that Kevin shares her gift, and they set out across Ireland, disguised as rats, and guided by fellow rats to ""little old lady"" Lizzie. The eccentric woman sends them on a quest north to stop the krools, ravenous monsters responsible for the Earth's ice ages. The pair races against time (Kevin is about to turn 15, when all Switchers have to choose their final form) and U.N. warplanes seeking alien invaders, to halt the global icing. In occasionally poetic language (which may need some explaining to younger readers), Thompson interweaves elements from mythology and science fiction with insights into animal nature to create a coming-of-age fantasy that, like Peter Pan, ends with an open window and, for many readers, a lump in the throat. Ages 8-up. (May)