1. Editorial

   • W. Dörfler

   EditorialNotes Pages: iii - iii

2. In memoriam Nicolas Herscovics 1935–1994

   • Jacques C. Bergeron

   Announcement Pages: v - vi

3. A model for nurturing and assessing multidigit number sense among first grade children

   • Graham A. Jones
   • Carol A. Thornton
   • Ian J. Putt

   OriginalPaper Pages: 117 - 143

4. Learning opportunities and negotiating social norms in mathematics class discussion

   • Jane-Jane LO
   • Grayson H. Wheatley

   OriginalPaper Pages: 145 - 164

5. Modalités de la pensée mathématique d'élèves de douze ans devant des problèmes de pavages

   • Christine De Block-Docq

   OriginalPaper Pages: 165 - 189

6. On fractions and non-standard representations: Pre-service teachers' concepts

   • Helen A. Khoury
   • Rina Zazkis

   OriginalPaper Pages: 191 - 204

7. The effects of using graphing calculators to enhance college students' performance in precalculus

   • Antonio R. Quesada
   • Mary E. Maxwell

   OriginalPaper Pages: 205 - 215