1. The probabilistic abacus

   • Arthur Engel

   OriginalPaper Pages: 1 - 22

2. Deformation and the four card problem

   • Thomas C. O'Brien

   OriginalPaper Pages: 23 - 39

3. Verbal cues as an interfering factor in verbal problem solving

   • Perla Nesher
   • Eva Teubal

   OriginalPaper Pages: 41 - 51

4. Natural numbers and groupings

   • Erich Wittmann

   OriginalPaper Pages: 53 - 75

5. Criticism in the mathematics class

   • J. D. Gray

   OriginalPaper Pages: 77 - 86

6. A computer language for teaching introductory logic

   • R. M. Cater
   • H. W. Johnstone Jr.

   OriginalPaper Pages: 87 - 91

7. The cycloid

   • Mario Barra

   OriginalPaper Pages: 93 - 98

8. A model of the symmetric group S₄ used as a means of teaching fundamental algebraic concepts

   • H. P. Hahn

   OriginalPaper Pages: 99 - 111

9. Introducing the geoboard

   • J. B. Harkin

   OriginalPaper Pages: 113 - 118

10. An experience of the Czechoslovakian experimental center

    • J. Vyšín

    OriginalPaper Pages: 119 - 123

11. Errata

    Erratum Pages: 125 - 125