When Max discovers that the lunch he's been looking forward to is missing, he and Ruby embark on a search for it.

"Amelia Bedelia loses her tooth . . . and then she loses it again. But it's finders keepers in the end"--

"In her chapter book debut, Nancy Clancy must find the culprit when a prized possession goes missing at school"--

When a bear loses his bright red scarf in the woods, it is found--and lost again--by a series of animals that use it to keep warm or to have fun, but they disagree over who really owns it.

"Third-grader Aven Green has been solving mysteries for a whole month, cracking such cases as The Mystery of the Cranky Mom. But can this perceptive detective solve two cases at the same time? First her teacher's lunch bag disappears. Then Aven's great-grandma's dog goes missing. Fortunately, since Aven was born without arms, all the "arm" cells went to her super-powered brain instead. (That's her theory.)"--

When second-grader Eugene's favorite comic book goes missing, he blames his best friend Charlie even though he has no evidence.

When someone keeps stealing Jack-o'-lanterns and a mysterious haunting begins at her Aunt and Uncle's old farm, Truly and the other Pumpkin Falls Private Eyes work to uncover the cause behind the fall shenanigans in their home town.

When Penelope Rex brings home Walter, the class goldfish, for the weekend, she is not sure how to feel, but when Walter goes missing, Penelope searches high and low for her fishy classmate.

"Leo isn't just a stuffed toy, he is Henry's best friend and brother. But when the two are accidentally separated, no one in Henry's family believes Leo is real enough to find his way home"--

While on an underwater adventure seeking sunken treasure, Flat Stanley finds a dolphin trapped in a net.