While visiting New York's Yankee Stadium with Kate's mother, cousins Mike and Kate decide to investigate the rumor that the ghost of Babe Ruth is haunting the stadium.

While visiting Houston, Texas, Mike and Kate tour the Johnson Space Center with an astronaut in the morning and at the Houston Astros' ball game that evening, the cousins search for the person who steals the astronaut's moonrock when he arrives at the stadium to sign autographs.

Next up to the plate—book #6 in our early chapter book mystery series, where each book is set in a different American ballpark! 
Ivy-covered walls—they're the most famous part of the Chicago Cubs' historic ballpark, Wrigley Field. Mike and Kate can't wait to get down on the field to see the ivy for themselves. But when they do, they're horrified to discover patches of the ivy have been ripped away! Who would want to sabotage the...

Cousins Mike and Kate investigate after someone threatens to tamper with the scoreboard right before the Colorado Rockies' season opener.