Project based learning is 21st Century learning. This is a comprehensive lesson plan for "Dinosaurs Before Dark", the first book in The Magic Treehouse series by Mary Pope Osborne. As the class progresses through the book chapter by chapter, students answer comprehension questions, conduct research on the Cretaceous Period, design and engineer STEM projects and use their knowledge to create a final project to present to the class. Throughout the unit, the 4 C's are covered - Critical Thinking, C