THIS BOOK IS A COLLECTION OF MATERIALS AND IDEAS ABOUT THE NEWER METHODS OF MATHEMATICS TEACHING BY A GROUP OF TEACHERS AND STUDENT-TEACHER LECTURERS. REPORTS FROM ACTUAL LESSONS AND VARIED ILLUSTRATIONS OF CHILDREN'S WORK MAKE UP A SIGNIFICANT PORTION OF THIS BOOK. THE MATHEMATICS IS PRESENTED IN A STYLE AND MANNER WHICH ENCOURAGES THE READER TO PURSUE HIS OWN HYPOTHESES IN THE WAY THAT CHILDREN DO. THE AIM OF THE COMMITTEE IN WRITING THIS BOOK WAS TO STIMULATE EXPERIMENTS IN THE TEACHING OF MATHEMATICAL CONCEPTS AND THE PRESENTATION OF ACTIVITIES IN THE CLASSROOM. THE MATERIALS REPORTED ARE GROUPED INTO THREE CATEGORIES--(1) COMMITTEE REPORTS OF CLASSROOM MATHEMATICAL ACTIVITIES AND CONCEPTS, (2) SIGNIFICANT COMMENTS BY THE COMMITTEE ON SOME LEARNING PROCESSES, AND (3) OTHER MATERIAL WHICH IN INCOMPLETE AND SUGGESTIVE FORM STIMULATES READERS TO MAKE MATHEMATICAL INVESTIGATIONS OF THEIR OWN. THIS DOCUMENT IS AVAILABLE FOR $12.50 FROM THE CAMBRIDGE UNIVERSITY PRESS, 510 NORTH AVENUE, NEW ROCHELLE, NEW YORK 10801. (RP)