Lecture-Tutorials for Introductory Astronomy, which was developed by the Conceptual Astronomy and Physics Education Research (CAPER) Team, is a collection of classroom-tested activities designed for the large-lecture introductory astronomy class, although it is suitable for any astronomy class. The Lecture-Tutorials are short, structured activities designed for students to complete while working in pairs. Each activity targets one or more specific learning objectives based on research on student difficulties in astronomy. Most activities can be completed in 10 to 15 minutes. The instructor's guide provides, for each activity, the recommended prerequisite knowledge, the learning goals for the activity, a pre-activity assessment question, an answer key, suggestions for implementation, and follow-up questions to be used for class discussion or homework.

Each year, over 200,000 students take introductory astronomy--hereafter referred to as ASTRO 101; the majority of these students are non-science majors. Most are taking ASTRID 101 to fulfill a university science requirement and many approach science with some mix of fear and disinterest. The traditional approach to winning over these students has been to emphasize creative and engaging lectures, taking full advantage of both demonstrations and awe-inspiring astronomical images. However, what a growing body of evidence in astronomy and physics education research has been demonstrating is that even the most popular and engaging lectures do not engender the depth of learning for which , faculty appropriately aim. Rigorous research into student learning tells us that one critical factor in promoting classroom learning is students' active "minds-on" participation. This is best expressed in the mantra: "It's not what the teacher does that matters; it's what the students do." Lecture-Tutorials for Introductory Astronomyhas been developed in response to the demand from astronomy instructors for easily implemented student activities for integration into existing course structures. Rather than asking faculty--and students--to convert to an entirely new course structure, our approach in developingLecture-Tutorialswas to create classroom-ready materials to augment more traditional lectures. Any of the activities in this manual can be inserted at the end of lecture presentations and, because of the education research program that led to the activities' development, we are confident in asserting that the activities will lead to deeper and more complete student understanding of the concepts addressed. EachLecture-Tutorialpresents a structured series of questions designed to confront and resolve student difficulties with a particular topic. Confronting difficulties often means answering questions incorrectly; this is expected. When this happens, the activities are crafted to help a student understand where her or his reasoning went wrong and to develop a more thorough understanding as a result. Therefore, while completing the activities, students are encouraged to focus more on their reasoning and less on trying to guess an expected answer. The activities are meant to be completed by students working in pairs who "talk out" the answers with each other to make their thinking explicit. At the conclusion of eachLecture-Tutorial,instructors are strongly encouraged to engage their class in a brief discussion about the particularly difficult concepts in the activity--an essential implementation step that brings closure to the activity. The onlineInstructor's Guidealso provides "post-tutorial" questions that can be used to gauge the effectiveness of theLecture-Tutorialbefore moving on to new material.