This is a SMSG inservice textbook for primary school teachers. One of the goals of the book is to promote the teaching of mathematics in accord with a conceptual development of mathematical ideas. The authors indicate that rote learning is frequently considered the only way to learn mathematics, especially for culturally deprived children. A feature of this text is an attempt to attend to learning problems that may be associated with the culturally disadvantaged. Other features of the text include sections in each chapter dealing with applications to teaching and frequently asked questions. Chapter topics include: (1) description of culturally disadvantaged children; (2) sets; (3) comparing sets; (4) whole numbers; (5) set operations; (6) introduction to geometry; (7) numeration-naming numbers; (8) addition; (9) multiplication; (10) subtraction; (11) division; (12) elements of geometry; (13) addition and subtraction techniques; (14) introducing rational numbers; (15) premeasurement concepts; (16) multiplication and division techniques; (17) measurement; and (18) structure. (MP)