This book is aimed at 8th graders. It is a second edition. Per book's introduction: This study of earth science begins with a study of space because the planets, stars, and all other heavenly bodies "float" in the "ocean of space," and these bodies affect one another. The elements that make up a study of earth science are space, sometimes called the celestial sphere; the atmosphere, the layers of air surrounding the earth; the lithosphere, the solid part of the earth; and the hydrosphere, the water that covers nearly three-fourths of the earth's surface. It includes the study of instruments used by scientists to examine and measure the environment, laws that operate within the environment, and a detailed and informational breakdown of each sphere of the earth with examples, pictures, tables, charts, scientists who contribute to each area of study, and scientific terms and theories.