The Berenstain Bears and the Haunted Hayride By Stan & Jan Berenstain

The cubs want to hold a Halloween Festival to raise money to help save Farmer Ben's floundering farm, but he's reluctant. After all, no self-respecting farmer would turn his place into a theme park! Things get spooky when Ben's long-dead ancestors show up. Will Ben's farm go bust, or will the ghostly forbears come to the rescue? 
 
- Goodreads Summary