** Abacus Activities
- Abacus Editor Greetings / Mary Lou Kestell & Kathy Kubota-Zarivnij
- Research Summary - About Subtraction
- LET'S DO MATH: Conceptual Representations of Subtraction
- Links to Manipulatives - Materials for Linear Models
- Links to Literature and Manipulatives / Pat Margerm
- LET'S DO MATH: Alternate Algorithms for Subtraction
- Professional Learning - Application to Your Classroom
- Professional Learning - Suggested Readings