Here is a classic time-travel mystery- with a twist. The Time of the Fireflies by Kimberley Griffiths Little is part of a series, but it doesn’t matter which order you read them in.
In the book, Larissa starts getting creepy phone calls on a disconnected old phone in her family’s antique shop. I immediately thought: “GHOSTS?!” But I’m not telling you what it is. You’ll have to read it! Larissa finds a series of clues, that eventually lead her to the muddy banks of the bayou, where at night, fireflies dance through the air. The fireflies take Larissa on a dangerous journey through time, where Larissa uncovers some of her family’s darkest secrets. Larissa learns that a treacherous curse still plagues her family. Does Larissa have what it takes to break the curse before history repeats itself?
I read this book towards the middle of fourth grade, so I’d say maybe age 9 and up? Definitely more geared towards girls, but I would never say no to anybody else.
Parents: If your younger kid is a really good reader, and if he/she has great comprehension skills, by all means! Let them read this! (You could also read it to them, or take turns reading!)