The Boxcar Children

#27 The Camp-Out Mystery by Gertrude Chandler Warner, 1992.

The Alden family has decided to go on a camping trip to a campground at a state park. From the moment that they arrive, though, strange things seem to be happening. When they stop for supplies, a woman Mr. Alden knows, Doris, seems oddly evasive when he tries to ask her about her sister, Hildy, and she makes the odd comment that she hopes nothing will spoil their trip. As they pull into the state park, they discover that the arrow on the sign pointing to the rangers’ station has been reversed to point the wrong way. Mr. Alden shrugs the incident off as a prank, but it’s only the beginning of the strange happenings.

The Aldens get to their camp site and notice that the place is a mess. Either the previous campers were pretty messy, or they left in a hurry. The Aldens clean up the site and set up their tents. (The description of how they set up camp is actually somewhat educational because they talk about things to look for when choosing a campsite, how they have to check the ground for rocks and tree roots before setting up their tents and why they should avoid places where it looks like rain water might pool and why it can be dangerous to set up a tent under a tree if there is a lightning storm.) Later that night, Violet is woken by the sound of music. At first, she thinks that it must be some nearby campers, but it sounds too loud and too close. When she and Jessie get up to investigate, the sound stops.

Later, the kids see strange lights in the woods, and things disappear or are moved around at their campsite. When Mr. Alden realizes that someone has been sneaking into their camp and taking things, he suggests that they might want to leave the park, but the kids say that they’d rather stay because they’re still enjoying themselves. Then, Mr. Alden injures his ankle when he’s startled by another blast of loud music and part of the path he’s on gives way because the dirt was loosened by rain. The children are prepared to leave when their grandfather is injured, but to their surprise, Mr. Alden says that he’d rather stay, too.
Who is doing all of these things and why? Is it the unfriendly Hildy, who lives alone in a cabin and wants everyone to leave her alone? Or maybe her seemingly-helpful neighbor, Andy, for reasons of his own? Could Doris be responsible? What about the Changs, a family camping nearby who seemed disappointed that they didn’t have the campground to themselves?
There are some environmental themes and lessons in the story. The Aldens frequently pick up litter that other campers and hikers leave behind. There is also an explanation that the reason why part of the path Mr. Alden was on collapsed due to erosion because there are no trees along that section of path; tree roots help secure the soil so that it doesn’t wash away. After the mystery is solved, Mr. Alden decides to donate some trees to the park, and the kids talk about adding more trash cans and a recycling center to help solve the litter problem.
The book is available to borrow and read for free online through Internet Archive.