This book is a collaborative project between the National Aeronautics Space Administration (NASA) and the National Council of Teachers of Mathematics (NCTM). It has two complementary goals: to provide classroom-tested lessons that effectively model the vision of the NCTM Standards and to focus on the exciting problems that arise out of NASA's activities. The lessons contained within this document are couched in an aerospace setting to motivate students to become involved with and connected to mathematical concepts, skills, and applications. Activities and lessons can be used independently to show how mathematics is used in the space industry. Many lessons are linked to form in-depth investigations that can be used in a variety of ways. The investigations are designed to become potential replacement units for parts of the present school curriculum. Chapters include: (1) "Lunar Exploration"; (2) "How Big Is Our Neighborhood?"; (3) "The Speed of Light"; (4) "Aeronautics"; and (5) "Mission To Planet Earth". (ASK)