In Memory of Adri Treffers
Op de trappen bij Utrecht Overvecht, leunend op een rekenrek.
It is with sadness that we learned of the passing of Prof. Adri Treffers (June 22, 1935 – January 6, 2026). Treffers was professor of domain-specific educational theories for arithmetic and mathematics at Utrecht University from 1989 to 1998. His vision on arithmetic and mathematics education was groundbreaking and influential in Dutch educational practice. He obtained his PhD on May 26, 1978, at Utrecht University: “Wiskobas doelgericht. Een methode van doelbeschrijving van het wiskundeonderwijs volgens wiskobas” (Wiskobas goal-oriented. A method of goal description in mathematics education according to Wiskobas).
During those years, he worked at the IOWO and the department “Development of Mathematics Education and Education Computer Center” (OW&OC), precursors of the Freudenthal Institute at Utrecht University.
In his influential publication ‘Three Dimensions’ (1978, a translation of his thesis), Treffers set the foundation for realistic mathematics education by describing its five characteristics: 1) Use of contexts, 2) Use of models, 3) Students’ own productions, 4) The interactive nature of the learning process, and 5) The interconnection of learning areas.
We remember Adri Treffers as a remarkable personality who inspired colleagues, teacher educators, and teachers with rich problems and innovative teaching methods.
- Treffers, A. (1987). Three dimensions. A model of goal and theory description in mathematics instruction – The Wiskobas project. Dordrecht, the Netherlands: D. Reidel Publishing Company.
- Treffers, A. (1987). Integrated column arithmetic according to progressive schematisation. Educational studies in Mathematics, 18(2), 125-145.
- Van den Heuvel-Panhuizen M., Drijvers P. (2020). Realistic Mathematics Education. In S. Lerman (Ed.) Encyclopedia of Mathematics Education. Cham, Switserland: Springer.
