This teachers manual accompanies a mathematics textbook, written in Portuguese, for third graders. It closely follows the objectives and methodology of the major curricula used throughout the schools in the United States. The 11 chapters deal with: numeration (0-999,999); addition with and without regrouping; subtraction with and without borrowing; commutative and associative properties; length, time, weight, capacity, and temperature measurements; money; geometric figures; perimeter and graphs; fractions; multiplication; division; and word problems. For each chapter the guide contains a discussion of objectives, an introduction, vocabulary, activities, an evaluation, a review, and answers to problems in the textbook. (RH)