This grade 3 mystery fiction reading unit (level M) is about the mystery of who is writing the word "beware" around a family's new house. Students learn about mystery fiction as a literary genre and do a literary analysis that focuses on mood. The unit contains teacher support pages, a reading selection with supporting illustrations, and activities to guide students in close reading of the text. Students also gain practice applying topic and academic vocabulary. The unit concludes with a reading comprehension activity and a text-based writing activity.