The product is a lot of 4 books from the "Scooby-Doo and You: A Collect the Clues Mystery Ser." series. It includes a bonus book  The books are in trade paperback format, with an intended audience of young adults and adults. The first edition was published in 1996 by Scholastic, Incorporated in the United States. Each book is a mystery novel with illustrations and a total of 61 pages.

The case of the wrestlers ghost

The case of the lost lumberjack

The case of the seaweed monster

Bonus cartoon network Haunted castle

615 #36