A serious illness is sweeping through town. Why are people getting sick? What is the source of this disease? With this problem-based learning unit, students become public health workers as they track down the source of a mysterious illness. Working in teams to solve the real-world problem and present their findings, they experience genuine, higher order learning. Decisions they make affect the outcome of the simulation. The activities combine science, social studies, math, research, thinking, cooperation, and speech skills in one great unit. This guide includes everything you need--teacher's directions and student information in the form of memos and medical reports.This open-ended scenario will draw students into a real-life drama. Allow your students to solve more real-life problems in Crime Scene Detective, Detective Club, Mystery Science, and The Great Chocolate Caper. Grades 5-8