Stacy Palen knows that introductory astronomy may be the only science course some students take in their college careers, so it's their best chance to develop scientific literacy. Education research shows that the best way to attain scientific literacy is through active learning. Understanding Our Universe, Fourth Edition makes it easier for instructors to help students understand the concepts and learn to value science by providing activities that can be used before, during, and after class. By expanding her pedagogy to include What If scenarios and What an Astronomer Sees figure captions, Stacy helps students build scientific literacy and to think critically about science in the media.