The research reported here was designed to investigate the critical role played by certain factors implicated in the mental representation of text, and to establish whether their role varies significantly as a function of developmental age. Specifically, it was decided to analyse, in a sample of 180 subjects was selected from three different age groups (7, 10 and 18 years of age respectively), the role of such factors in mediating and influencing the generation of the inferences needed to understand a piece of text characterised by a sequence of information which flows in a logical order, but leads to a conclusion which is contrary to the expectations evoked by the text. In line with this objective, it was decided to take into account factors related to encoding (added information about the key object – a title), those involved in recall (inferential tests regarding the object and action of change), as well as purely metacognitive factors, such as evaluation of one’s own comprehension and awareness of textual incongruence, whose presence, according to our assumptions, should facilitate the formulation of inferential hypotheses. It would thus seem that inferential processing is powerfully influenced both by cognitive and structural factors, factors which can play a role during both encoding and recall. The results reported here tend to confirm the hypothesis that there is indeed a significant developmental trend in the role played by those factors involved in the coherent representation of text and in the formulation of inferences. The data suggest that children in the youngest age group obtain the greatest advantage from clues in reaching a more correct representation of the text concerned. It is concluded that inferential processes do not serve only to make connections between propositions, but to construct a coherent mental representation of text (Kintsh, 1994; Zwaan, 1994, 1996)