Research Ideas for the Classroom is a three-volume series of research interpretations for early childhood, middle grades, and high school mathematics classrooms. Each volume looks at research from the perspective of the learner, the content, and the teacher, and chapters are co-authored by a researcher and a teacher. Chapter titles in the middle grades volume are: (1) Students' Thinking: Middle Grades Mathematics (Peter Klossterman and Patricia Haynes Gainey); (2) The Role of Affect in Teaching and Learning Mathematics (Laurie E. Hart and Jamie Walker); (3) Number Sense and Related Topics (Judith T. Sowder and Judith Kelin); (4) Insights from Research on Mathematical Problem Solving in the Middle Grades (Diana Lambdin Kroll and Tammy Miller); (5) Measurement, Probability, Statistics, and Graphing (George W. Bright and Karl Hoeffner); (6) Multiplication and Division: From Whole Numbers to Rational Numbers (Anna O. Graeber and Elaine Tanenhaus); (7) Current Research on Rational Numbers and Common Fractions: Summary and Implications for Teachers (Nadine S. Bezuk and Marilyn Bieck); (8) Teaching and Learning Decimal Fractions (Douglas T. Owens, Douglas B. Super); (9) Learning and Teaching Ratio and Proportion: Research Implications (Kathleen Cramer, Thomas Post, and Sarah Currier); (10) Prealgebra: The Transition from Arithmetic to Algebra (Carolyn Kieran and Louise Chalouh); (11) Geometry: Research and Classroom Activities (Dorothy Geddes and Irene Fortunato); (12) Technology: Implications for Middle Grades Mathematics (Robert J. Jensen and Brevard S. Williams); (13) Models of Instruction (William M. Fitzgerald and Mary Kay Bouck); (14) Planning and Organizing the Middle Grades Mathematics Curriculum (Anne L. Madsen and Kendella Baker); (15) Classroom Interactions: The Heartbeat of the Teaching/Learning Process (Mary Schatz Koehler and Millie Prior); (16) Assessment and Evaluation for Middle Grades (Norman L. Webb and Carol Welsch); and (17) Teacher as Researcher (Gillian Clouthier and Darlene Shandola). The tables of contents for the early childhood and high school volumes are included. (MKR)