The Alden children are staying at the New England farmhouse where their grandfather grew up. There are many stories and legends about the old farm, and there's a woodshed near the house that holds a surprising secret... a secret that dates all the way back to the Revolutionary War!

While helping fix up the old house their cousins have bought, the Aldens hear stories about its being haunted and find evidence suggesting that there may be a ghost there.

The Aldens are spending spring break on a beach, but they aren't just soaking up the sun. They're protecting an endangered species! Their job is to mark sea turtle nests so the eggs can be moved to a safe place to hatch, but someone is digging up the eggs without permission. Can the Boxcar Children figure out what's going on and help save the sea turtles?