Children's Lit, Adventure, Mystery
The Boxcar Children was penned by a first-grade teacher who was specifically writing for kids, which places it firmly in the children's lit category. One way that she appealed to young people was by making the story easy to read; another way was by making the plot exciting. The Alden children's adventures on the road and in the woods are romanticized quite a bit. If the author had written a realistic depiction of four orphans living in a boxcar, the book would be a lot more depressing (and, therefore, more of a family drama or a tragedy).
The book is the first volume in an epic series of The Boxcar Children mysteries. While there's not really a big, overarching mystery that gets solved in this first story, it does have a lot of mysterious elements. First of all, many mysteries lurk in the background of the story. How did the Boxcar Children's parents die, anyway? And why do the kids assume their grandfather is mean? Many of the characters keep secrets, too, like when Mr. Alden doesn't tell his grandchildren his true identity.
Many smaller mysteries drive the plot. Some are pretty suspenseful—for example, who is the person that Jessie and Henry hear in the woods late at night?—while others are a little less exciting, like the origin of Watch the dog. Many of these questions get resolved at the end of the story; we find out that the "intruder" was actually Dr. Moore, and that Watch was lost when his owner sold him. Glad we cleared that up.