Madge Bettany, along with her twin brother Dick and younger sister Joey, are left struggling financially after the death of their guardian. Dick works in India, in the Forestry Department (the Forests), and is unable to keep them on his pay, so Madge decides to run a school.
England is too expensive and India unsuitable for Joey's fragile health so she decides to set up the school by a lake in the Austrian Tyrol, where they had been on holiday five years before. The school opens with nine pupils and two mistresses but quickly grows, with pupils of several nationalities attending.
With numerous pranks and adventures the girls strive to make the school truly English.
Simone Lecoutier, Mlle La Pâttre's cousin, is desperate to become friends with Joey, and goes to the lengths of cutting her hair in order to please the object of her affection, although Joey believes it all to be "idiotic nonsense".
Juliet Carrick joins the school and quickly becomes a troublemaker, disobeying the Head when a film crew comes to the lake. Grizel Cochrane makes an enemy in the form of an ill-bred lady from Berlin, nicknamed 'Frau Berlin' by the girls, while she and Joey are out buying a birthday present for Madge.
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giving everything away!