| Although technology is integrated in education, little is known about the relationship between the use of technological tools and cognitive development, and the way in which the teacher ?orchestrates? tool use. This issue is addressed for the case of mathematics education. The theoretical framework consists of activity theory and the instrumental approach. In a design research methodology, an innovative instructional sequence using applets is developed and tested in grade 8. The results include a local instruction theory, an explanatory theoretical framework for tool use in education, and theoretically and empirically founded knowledge concerning orchestration by the teacher. |
