Mystery of the Mixed-Up Zoo

The Alden children investigate various mix-ups at a zoo run by their grandfather's friend in an effort to save it not only from pranksters but also from the town council.
The Boxcar Children try to find out who's responsible for causing some trouble at Edward Marlow's zoo.

Mystery of the Stolen Boxcar

Someone has stolen the Aldens' boxcar! Can they get it back?
The Alden children plan to ride in their boxcar at the Greenfield Founders' Day Parade, but the newly refurbished boxcar is stolen a couple of days before the big event.