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.
While visiting Michigan's Upper Peninsula to prepare their Great-aunt Sophie's big old house for sale, the Boxcar Children encounter a mystery involving a valuable ring supposedly hidden somewhere in the house.
"When the Aldens take up the case to investigate if a catastrophic oil spill that affected hundreds of species could have been prevented, they are led on an adventure to help other endangered animals around the world"--OCLC.
"Wherever the Boxcar children go, they discover haunted havens, spooky sights, and mysterious old legends come to life! Here are three of their ghostliest adventures"--Back cover.
"Learning about paleontology and fossil hunting under renowned scientist Dr. Iris Prez while attending summer camp in Colorado, the Aldens investigate an outbreak of strange events that local superstition attributes to a bigfoot creature roaming the valley"--OCLC.