This series offers explanations for various mysterious encounters. Color sidebars offer definitions and explanations, and each ends with a 1-2 pages of notes, a one-page glossary, and a two-page bibliography. These are thin books and their format and illustrations might attract a younger audience; however, most students below middle school would lack the ability to create the type of questions necessary to accept or refute the theories in them. While sidebars are designed to develop critical thinking skills to provide alternative explanations, it will take a very capable teacher to develop these into research projects.