This textbook is the last volume in the Pathways in Science series, designed to meet the demands of the modern tendency to introduce science as an essential part of the elementary-school curriculum by presenting a course of carefully graded problems in science for Grades I to VI. "Our Earth and Its Story" has been designed to assist the child in orienting himself intelligently with respect to the universe about him and to give him an acquaintance with certain of the basic principles and concepts of science. Thus, the book is intended for the children who will have opportunity to extend their study of science, as well as those who are forced to withdraw from school at an early age. The unit utilizes the concepts and meanings developed in previous books and gives them further development.