The seventh installment of New York Times bestselling author Mike Lupica's Zach & Zoe Mysteries--a sports-themed chapter book mystery series perfect for fans of Cam Jansen ! In this seventh sports-themed mystery, eight-year-old twins Zach and Zoe go on a school field trip to the National Baseball Hall of Fame in Cooperstown, New York. On their tour, they discover one of the display items is missing from its case, and with the help of their classmates, they work together to figure out what happened. Once again, bestselling author Mike Lupica charms his youngest readers yet with a detective duo who can swing for the fences and catch the culprit in one fell swoop. With a recipe of equal parts sports and mystery, the Zach & Zoe Mysteries break fresh ground for an author who has been called the greatest sportswriter for kids. Mike Lupica  is a prominent sports journalist and the  New York Times -bestselling author of more than forty works of fiction and non-fiction. A longtime friend to Robert B. Parker, he was selected by the Parker estate to continue the Sunny Randall and Jesse Stone series. Chapter One Zach and Zoe were playing catch in their backyard when Zoe asked her twin brother, “What are the two greatest words in the English language?” “That’s easy,” Zach said. “Ice cream.” Zoe grinned at him. They both knew how much he loved ice cream. “We haven’t even had dinner yet,” Zoe said. “It’s too early to be thinking about dessert.” “Ice cream isn’t just dessert,” Zach argued. “If I were in charge, you’d be able to have it with every meal of the day. Including breakfast.” It was finally spring in Middletown. But the beautiful, warm day they were having made it feel like summer. “Okay, think about two more words that are just as great,” Zoe said. “Baseball!” Zach said, before going into a big windup and firing the ball in his sister’s direction. “That’s just one word, silly,” Zoe said, catching the ball in her mitt. “Try again.” “Uhhh . . . snow day?” Zach said. “Two words that describe one perfect day.” Zoe reached her hands out at her sides and looked up at the clear blue sky. The trees in their backyard were blowing in the breeze. “How can you even think about snow on a day like this?” Zoe said. “Okay, you got me,” Zach said, lifting his hands in surrender. “I can’t always read your mind, you know. Why don’t you just tell me the two words you’re thinking of?” Zoe wound up and threw a perfect pitch across the yard into the pocket of Zach’s glove. It was the kind of throw that made Zach think his sister had the best arm of any eight-year old in Middletown. “Field trip,” Zoe Walker said. “Oh, yeah!” Zach Walker said. “Field trip is even better than ice cream, especially when it’s a baseball field trip.” The third graders from Middletown Elementary were taking just such a field trip the next day. The National Baseball Hall of Fame museum in Cooperstown, New York, had recently started having small traveling museums visit towns around the country. It had begun with a few exhibits of famous photographs from baseball history. Now they were bringing more items on tour. Zach and Zoe had visited the Hall of Fame with their parents during the summer. But the museum added new items all the time. The twins were excited to explore the exhibits with their classmates. “What sorts of things do you think they’ll have there?” Zach asked Zoe. Zoe thought back to when she and her brother visited the museum last summer. There were displays of baseballs and bats and gloves and spikes that had once belonged to the greatest baseball players who ever lived. Zoe’s favorites were the uniforms of the players who had been voted into the Hall of Fame. The Walker twins couldn’t believe that Middletown had been selected to host one of the traveling museums. It had all started with a letter from their dad, Danny Walker, to the people in charge of the Hall of Fame. The museum held a contest as a way to choose which towns they’d be stopping at on their tour. So Danny Walker, with the help of his kids, decided to enter. He had to write a letter to the Hall of Fame explaining why Middletown should be chosen. In the letter, he wrote about the great Hank Aaron, who had broken Babe Ruth’s all-time home run record back in the 1970s. At one time, Hank had played for a team called the Indianapolis Clowns, before he got to the major leagues. The Clowns used to travel all over the country to play games. Early in the 1950s they had come to Middletown, which had a minor league team known as the Middletown Thunder. Not only did Hank Aaron play a game against the Thunder at Middletown Park, he hit a home run that cleared the fences and traveled nearly all the way to the Middletown River. Because Hank Aaron went on to become a legend, that game between the Clowns and the Thunder was remembered as the most famous baseball game ever played in Middletown. Danny Walker wrote about that game in his letter. He explained how Middletown w