The Dragonfly Pool by Eva Ibbotson

A spirited, sheltered girl from an aristocratic English family is sent to an experimental, international boarding school where she makes firm friendships with children from many lands and becomes particularly close to a refugee royal; when his small country is threatened by political upheaval and war, she and her schoolmates draw on courage, creativity and loyalty—staging performances and risking everything—to help those they love and to discover what home and bravery truly mean.

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