The Box-Car Children

Four orphans — Henry, Jessie, Violet, and Benny — discover an abandoned boxcar and move in, embarking on a life of self-reliance and hard work. They also enter a world of freedom and adventure. When Violet falls ill, they're forced to take her to a doctor, even though they'll risk losing their independence by getting a grown-up involved.
Gertrude Chandler Warner read this story to her students and rewrote it many times to make sure that it would be both engaging and easy to read. The Box-Car Children was so successful that she published 18 sequels. Warner noted that the book "raised a storm of protest from librarians who thought the children were having too good a time without any parental control! That is exactly why children like it!" Ranked among the all-time "Top 100 Chapter Books" in a School Library Journal survey, The Box-Car Children is also among the National Education Association's "Teachers' Top 100 Books for Children."