The boys began the attempt Friday morning at the Bounce-a-Lot entertainment center southwest of Detroit in Flat Rock. They bounced two at a time in shifts for 24 hours in an inflatable castle.
Ten-year-old Mason Brott says the bouncing wasn't as tough as he thought it would be.
Guinness World Records must still authenticate the record, a process that could take months. The boys, ages 8 to 11, decided to try to beat the bouncing record of 19 hours and 24 minutes, set nearly two years ago.