St.Clare's Series (Book 1 To 6 Box Set) by Enid Blyton

Throughout the various installments, such as The Twins at St. Clare's and The O'Sullivan Twins, the narrative introduces a memorable cast of classmates and teachers who challenge and support the twins. The stories emphasize the importance of integrity, hard work, and loyalty, often through humorous subplots involving practical jokes and schoolgirl "scrapes". By blending everyday academic struggles with the excitement of life away from home, the series remains a definitive example of mid-century British children's literature, celebrating the enduring bonds formed during one's school years.