Response categories
We elaborated a system of descriptive categories to analyse the products children
produced in order to illustrate their writing production for each of the requested ages
and the procedural and representational changes they introduced among writings for
successive ages. The coding system was based on the categories developed in the
previous drawing study (see Scheuer, Pozo, et al., 2001) by opening those categories
referring to the results of learning (we have not considered here the other components
of learning, i.e. conditions and processes) and by including a few new categories
specifically pertaining to writing (e.g. typography, writing extension). Table 1 presents
examples of all the product and change categories by presenting the coding of
fragments or complete productions. All the responses were coded by two of the authors
and controlled by an external collaborator. Agreement was high (.90%).