This teacher's guide for the SMSG text materials for grade 1 considers ten chapters: sets and numbers, numerals and the number line, sets of ten, introduction to addition and subtraction, recognizing geometric figures, place value and numeration, addition and subtraction, arrays and multiplication, partitions and rational numbers, and linear measurement. Mathematical background is presented for each chapter, followed by lesson plans detailing suggested activities and questions. Objectives, needed materials, vocabulary, and answers to worksheets are included. (MS)