In The Fifth At Malory Towers by Enid Blyton

Darrell returns to her senior year at Malory Towers and finds that greater responsibility and growing friendships bring new challenges: tense rivalries, a difficult new girl whose behaviour tests loyalties, busy school activities from games to drama, and the pressures of exams and prefect duties. Through mishaps, misunderstandings and kind deeds, Darrell and her friends learn about leadership, forgiveness and maturity as they navigate the ups and downs of boarding-school life.

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