This publication contains reference materials and activities for teachers in a staff development program in New York City, teaching grades 3 and 6. The program combines content and methodology. Sections in the publication include: (1) Student Verbalization Resources; (2) Manipulative Resources; (3) Probability, Statistics, and Graph Resources; (4) Resources for Instruction; (5) Estimation Resources; (6) Research Resources; (7) Mathematical Concept Development; and (8) Sample Mathematics Masters. Different sections contain different kinds of materials including background and evaluation materials, activities, lists, duplication masters, and teaching tips. (RH)