Dink, Josh, and Ruth Rose help catch the thieves who have stolen the treasure from the museum's mummy exhibit.

Nancy receives a letter meant for a British heiress who has the same name and, in her attempts to contact the other young woman, faces danger from a man who operates a Lonely Hearts Club mail fraud.

Presents ten cases in which the reader pits his wits against those of Encyclopedia Brown, an ingenious twelve-year-old detective.

It's gone! Oliver's boring blue beach bag is gone. Inside are his clothes, shoes, and a special seashell. All he has left is his beach ball. This is a perfect case for Nate the Great and his trusty dog, Sludge. But they don't find many clues in the sand and surf. What trail should they follow next? Follow the leader to find out!

The boys once again have jumped into the thick of a complicated mystery. Samuel Blacksone and his brother Ruel Rand live on adjacent properties, and it appears that one of them is out to hurt the other because they are both attacked. Frank and Joe soon learn that treasure is rumored to be hidden between the two properties, and as they investigate, they learn that others are involved in the apparent plot between the two brothers. Spooky mansions, secret...

Fifth-grader "Encyclopedia" Leroy Brown solves ten mysteries and, by putting the solutions at the back of the book, challenges the reader to do the same.

Nate the Great investigates the mysterious disappearance of the purple plastic octopus that his baseball team uses for second base.

Nate and his dog Sludge help Rosamond discover who has been tearing pages out of her books.

The Alden children help out at the Greenfield Ice Cream Barn and while learning to make ice cream and create new flavors, they help solve a mystery before the Barn gets shut down.

Mrs. Strook requests Nancy's help finding an old stagecoach she believes her uncle hid in her hometown of Francisville. Mrs. Strook believes the stagecoach houses a clue that will be valuable for the town! Can Nancy help her find the missing stagecoach?