Marie, Noelle, and all their friends are back to solve more mysteries---big and small. This year, the girls struggle all year long to earn enough money to travel to Hawaii where their biggest mystery ever awaits them. These popular books appeal to girls who love to solve puzzles, uncover clues, and crack cases! Along with Marie and her best friend, Noelle, girls must figure out which clues in the story will help solve the mystery and which ones are red herrings--those false leads that can send a reader in the wrong direction. A repeating cast of characters and real-life girl situations allow readers to connect with the stories they're reading. Once the reader solves a mystery, she can tear open a case folder in the back of the book to check her answer.