I first read Roller Skates (1937) at around age 11, and The Year of Jubilo (1940) somewhere in junior high school (that is, middle school). I'm blogging them here because of Yuletide.
In New York City in 1890, 10-year-old Lucinda Wyman is the youngest of five children. Her four older brothers range from a teenager in prep school to a grown man who's headed out west for a career in mining. Lucinda, a book-loving tomboy, is an afterthought, considered at best an amusing pet and at worst an annoying duty, understood only by her Irish nursemaid, Johanna, and her beloved Uncle Earle. When Mrs. Wyman becomes ill and needs to recover in a milder climate, Lucinda is left behind to stay with Miss Peters, a teacher at her school, and Miss Peters' seamstress sister.
The Misses Peters prove to be ideal guardians from Lucinda's viewpoint. Once her lessons are done, she's allowed to roam at will along the streets of New York, usually on her roller skates. She makes friends with a number of people of whom her parents - and even more so, her bossy and uptight Aunt Emily - would not approve, including the cab driver who first takes her to the Miss Peters' boarding house, a local policeman, the son of an Italian immigrant fruit seller, the four-year-old daughter of the impoverished family upstairs, a girl of her own age who is the grandchild of a married couple of actors, and a mysterious "Asiatic" woman whom Lucinda calls "Princess Zayda."
During the course of the year, Lucinda learns a great deal about life - and death. Tragedy strikes twice, and by the time her parents are due home, she isn't the same child she was. The ending is bittersweet: at least one other blogger was convinced, as a child, that Lucinda killed herself, because she says that she doesn't want her next birthday, and that she wants to stay 10 always.
When the story resumes in The Year of Jubilo, Mr. Wyman has died, but even before that, his businesses were failing. Mrs. Wyman, thirteen-year-old Lucinda, and the three sons who still live at home can no longer afford to live in New York. They still own a summer home in Maine, and the family moves there permanently. Every member of the family suffers at first from loss of Mr. Wyman and of their well-to-do lifestyle, but they gradually start to make a go of it. The boys take up lobster fishing (they sell the lobsters to restaurants as far as Boston) and gardening, Mrs. Wyman turns to housekeeping and mending, and Lucinda takes up cooking (with predictably comical results at first) and whatever else she can talk her brothers into letting her do.
Lucinda faces a great deal of resistance from her brothers, especially her next-older brother Carter, who is bitter at being pulled from his prep school. Although some of Lucinda's growing maturity here is depicted as her becoming less of a hoyden, she still remains very much a stubborn and decidedly un-meek person - and a passing remark by the narrator at one point indicates that she eventually goes to college, which was not a given even for a girl of the upper middle class at the time.
( More discussion, some including serious spoilers - and notes about problems with the stories )
Roller Skates won the Newbery Award in 1937 and is thus still in print in paperback. The Year of Jubilo is more difficult to find, but I bought a copy for less than $10 from AbeBooks.