This volume contains preliminary versions of five of the chapters prepared by the SMSG curriculum project for use in grades 7 and 8. The first four chapters and the tenth chapter in the sequence are presented. The sample chapters in this volume illustrate a number of aspects of the curriculum project: (1) association of ideas of number and space through coordinate geometry; (2) early introduction of the function concept; (3) development of flow charts and algorithms as an introduction to the role and use of computers in modern society; (4) attention to the role of mathematical models for physical situations; and (5) introduction of concepts of probability. (MP)