This paper describes aspects of 13 year-olds’ activity in mathematics as emerged during the implementation of proportional geometric tasks in the classroom. Pupils were working in pairs using a piece of software specially designed for multiple representation (symbolic and graphical) of the variation in parametric procedures with dynamic manipulation of… (More)

@inproceedings{Psycharis2005NormalisingGC,
title={Normalising Geometrical Constructions: a Context for the Generation of Meanings for Ratio and Proportion},
author={Georgos Psycharis},
year={2005}
}