Giant Yo-Yo Mystery by Gertrude Chandler Warner

CHAPTER 1
An Unhappy Neighbor
    “Hey, everyone!” six-year-old Benny Alden cried as he ran into the living room dragging an old red yo-yo by its string. “You’ll never guess what I just did!”
    Benny’s ten-year-old sister, Violet, glanced up from her book. “What did you do, Benny?”
    “Yes, tell us,” twelve-year-old Jessie said eagerly. She and fourteen-year-old Henry were in the middle of a game of checkers.
    Their grandfather, James Alden, set his newspaper aside. “Whatever it is must be pretty exciting. You’re all out of breath, Benny.”
    Benny grinned. “I know,” he said, panting. “And my news is exciting.” He took a deep breath, then said, “I just broke my own record!”
    “Record for what?” Henry asked.
    “Yo-yoing!” Benny held up his yo-yo. “My old record was 42. But I just made this yo-yo go down and up 57 times!”
    “That’s wonderful, Benny,” Jessie said.
    “It sure is,” Grandfather agreed. He looked closer at the yo-yo in Benny’s hand. “Hey, where did you get that yo-yo?”
    “I found it out in the boxcar,” Benny replied.
    Back before the children had come to live with their grandfather, they lived in an old boxcar. Their parents had died and they didn’t know their grandfather. They were afraid he’d be mean, so they ran away. They found an old boxcar in the woods and decided to live there.
    When their grandfather found them, the children discovered he wasn’t mean at all.
    He brought them to live with him. He even had their boxcar moved to his backyard so they could play there anytime they wanted to.
    Grandfather picked up the yo-yo and turned it around in his hand. The initials J.A. were carved into one side of the yo-yo.
    “This looks like my old yo-yo,” Grandfather said with a smile. “I thought this was in a box of old toys in the basement. I wonder how it got out to the boxcar?”
    Benny looked the yo-yo over. “I bet I know,” he said after a little while. He pointed to some tiny gouges in the wood. “See the teeth marks? I think Watch found it in the basement and took it outside.”
    The Aldens’ dog slapped his tail on the floor and let out a friendly woof when he heard his name.
    “I’ll bet you’re right,” Henry said.
    “Good detective work, Benny,” Jessie said, scratching Watch behind the ears.
    The Aldens were known for their detective skills. They had solved many mysteries since coming to live with their grandfather.
    “Well, I’m glad you found it,” Grandfather said, turning the yo-yo around in his hand. “I used to be quite good at this when I was a boy. I knew several tricks.”
    “Can you show us?” Violet asked.
    “I don’t know if I can still do this,” Grandfather said. “Let’s see …” He brought his hand up to his shoulder, flicked his wrist and sent the yo-yo down to the floor. It rolled along the carpet for a few feet, then Grandfather rolled it back up again.
    “Wow!” Benny said, clapping his hands. “What’s that trick called?”
    “It’s called ‘walk the dog,’” Grandfather said.
    “Can you show me how to do it?” Benny asked.
    “Sure,” Grandfather said. “First you have to learn to make the yo-yo ‘sleep.’”
    “Sleep?” Benny wrinkled his nose. “I thought only people and animals could go to sleep.”
    Grandfather chuckled. “Yo-yos can sleep, too. When a yo-yo sleeps, that just means it’s spinning at the bottom of the string. Like this.” Grandfather brought his hand up to his shoulder once again and sent the yo-yo down. The yo-yo stayed at the bottom of the string and spun around and around. It didn’t come back up until Grandfather turned his hand around and pulled it back up.
    “How did you do that?” Benny asked, wide-eyed.
    “Let me show you,” Grandfather said. He handed the yo-yo back to Benny. “Now, raise your arm up like you’re lifting a weight. Then throw your arm forward and drop the yo-yo.”
    Benny tried to do what Grandfather said, but the yo-yo just