Science, engineering, and technology permeate nearly every facet of modern life, and they also hold the key to meeting many of humanity s most pressing current and future challenges. Yet too few U.S. workers have strong backgrounds in these fields and many people lack even fundamental knowledge of them. This national trend has created a widespread call for a new approach to K 12 science education in the United States. From the Executive Summary of A Framework for K 12 Science Practices, Crosscutting Concepts, and Core Ideas A Framework for K 12 Science Education provides a broad set of learning expectations for students as they study science and engineering throughout the K 12 years. The Framework guides the writers of the forthcoming Next Generation Science Standards (NGSS); will influence curriculum, assessment, and teacher professional development decisions for years to come; and ultimately will help inspire new generations of science and engineering professionals and scientifically literate citizens. The handy Reader s Guide unpacks the three key dimensions of the Framework scientific and engineering practices, crosscutting concepts, and core ideas in each specific discipline allowing teachers, administrators, curriculum developers, university professors, and others to more easily grasp how the soon-to-be-released NGSS will differ from the current standards. Harold Pratt, a career science educator who was deeply involved in the development of the National Science Education Standards, offers the following for each chapter of the An overview with a brief synopsis of key ideas An analysis of what is similar to and what is different from the NSES A suggested action to help readers understand start preparing for the NGSS Now as a bonus the volume also includes four essays by key leaders in science education, each explains the Framework further. Rodger Bybee discusses scientific and engineering practices; Cary Sneider, engineering and technology core ideas; Richard Duschl, crosscutting concepts; and Joseph Krajcik and Joi Merritt, constructing and revising models. This primer is a critical companion to the Framework for science educators nationwide as they prepare to incorporate the upcoming standards into their teaching of science and engineering.