German boys work their way at English school . Under educational exchange system . Drawn from every part of Germany , a number of boys have joined the pupils at Berkhampstead School , Hertfordshire , under the international educational exchange system . The German schoolboys , whose ages average fifteen years , are taking their lessons with the English boys and are joining in the normal routine of the school . In return , they are working voluntarily , in the grounds and on surrounding farms . At present they are helping the Berkhampstead boys to construct a new playing field for the school . Photo shows , tthe German boys carting material for the new playing field they are helping the Berkhampstead boys to construct . 15 April 1936