The Adventures of the Red Tape Gang by Joan Lowery Nixon, 1974.
Hardcover editions of this book are called The Mysterious Red Tape Gang.
Mike’s father loves to read the newspaper every morning and rant about the stories that make him angry. It annoys him how little gets accomplished because there’s so much “red tape” involved. Take the case of their neighbor, Mr. Hartwell. He has a large bush that’s dangerously close to the corner of their street and has caused several accidents. The city wants him to cut it, but he refuses to do so out of meanness and stubbornness. Now, the city has to go through all kinds of red tape to make it happen.
His father’s rants give Mike an idea. Why not put the new clubhouse he and his friends are working on to good use and form a club to right the wrongs of their neighborhood and make all of that red tape unnecessary? Besides, cutting the Hartwells’ bush in the middle of the night would be a great joke on Mr. Hartwell’s nosy daughter, Linda Jean, who’s always hanging around, getting in the way of Mike and his friends.
Mike’s friends love the idea of being secret neighborhood heroes, but of course, it turns out to be harder than they expected. After trimming the Hartwells’ bush as best they can, they decide that instead of just cutting the bush, it would be better to move it to a completely different spot so there will be no need to cut it again when it grows out. But, Mr. Hartwell almost catches them in their midnight landscaping, and when Linda Jean finds Mike’s shears, they’re forced to let her into their club.
Their next project, boarding up the doors and windows of an abandoned house so that curious children won’t wander in and get hurt, also comes with complications. It seems that the house wasn’t quite as abandoned as everyone thought. Still, the Red Tape Gang accomplishes something even greater than just keeping kids out of the house and successfully keeps their identities secret. But while they’re congratulating themselves on the wonderful job they’ve been doing, they discover that their neighborhood contains far more serious problems than they originally thought. Their activities are also starting to come to the attention of the wrong people. And, for one member of the group, these problems hit dangerously close to home.
This was one of my favorite books when I was a kid. The descriptions of the kids’ midnight excursions are hilarious and make you want to cheer them on!
This book is currently available online through Internet Archive.
Our Teacher Is Missing by Mary Frances Shura, 1992.
Never Hit a Ghost with a Baseball Bat by Eth Clifford, 1993.
The girls explore the trolleys parked in the museum and admire the manikins dressed in old-fashioned clothing that are part of the displays in each trolley car, but more strange things happen. A teddy bear seems to speak to them, even though it isn’t the kind with a string and a talk-box. The manikins start to seem creepier. Mary-Rose and Jo-Beth are only armed with a baseball bat from one of the displays and the old teddy bear (which terrifies Jo-Beth). But, Mary Rose is determined to find the ghost, even if it’s the last thing she does!
The Dastardly Murder of Dirty Pete by Eth Clifford, 1981.
Harry Onetree and the girls find a ghost town with a hotel, an opera house, and several other buildings. Although Harry only means to look around for a little while, he forgets to set his parking brake (something else Mary Rose warns him about, which he ignores), and their car rolls backward into a ditch. Since it’s getting dark, they’re stranded in the ghost town for the night. But, they’re not alone there.
Scared Silly by Eth Clifford, 1988.
While the Onetree family is visiting the museum, a pair of shoes that once belonged to a Chinese emperor disappears. Like the two Onetree sisters, Gus considers himself the sensible brother and doesn’t take Razendale, the dreamier sibling, very seriously. He thinks Razendale ran off with the shoes as a prank. But, Erik, who seems more sensible than either of his uncles, says that they can’t just accuse him without proof. Gus provides them with an invention that could settle the whole matter, but that depends on whether or not they can trust Gus.
Just Tell Me When We’re Dead! by Eth Clifford, 1983.
The first place he goes is to an island in the middle of the lake near his house. The island has campgrounds and an amusement park, which is now closed for the season. Mary Rose and Jo-Beth, realizing where Jeff has gone, follow him there. But, the children are not alone on the island. When Jeff is captured by two criminals who are looking for loot that they stashed on the island years before, he has to keep his wits about him to find a way to summon help. Meanwhile, Mary Rose and Jo-Beth have no idea what they’ve just walked into.

The Ghost that Came Alive by Vic Crume, 1975.
They tell the kids that the house is supposed to be haunted and people can often hear the ghost of Andrea Cliff calling out in the night. The kids soon hear this spooky voice themselves, calling for help. Trapped in the house with the ghost and unfriendly people, the Blairs decide that they have to figure out what’s really going on, but the danger is worse than they know, and Jenny’s premonition of doom is getting stronger all the time . .
The Mystery in Dracula’s Castle by Vic Crume, 1973.
Alfie is an aspiring film maker. Specifically, he wants to make horror movies, and he talks his younger brother into playing the part of Dracula in his latest Super 8 film. Leonard is only a reluctant vampire because he doesn’t like horror movies. He really wants to be a detective, like Sherlock Holmes. Back home, he and his brother saw police investigating the scene of a robbery at a jewelry store, and he’s decided that he wants to investigate crimes like that. Soon after they arrive at the beach house, Leonard adopts a stray dog and names him Watson so that he can be his sidekick.
The Case of the Haunted Health Club by Carol Farley, 1991.
Flee Jay thinks this is spooky, but Clarice doesn’t believe in spirits. In order to investigate further, the two girls accept part time jobs helping the fortune teller and her nephew to clean up the building so they can move in new exercise equipment. “The spirits” continue sending warnings in the form of red dye in the Jacuzzi and threatening messages. Clever Clarice uses logic to point out how most of these things were accomplished but is surprised when Flee Jay reveals something that she overlooked.