Thanks to the help of the French National Agency for Research (ANR), manufacturers, researchers on spoken interactive systems and researchers in French language didactics have developed a software in order to help young French learners (students aged 6 to 7) to produce written texts. Our presentation, resulting from the conclusions of an investigation conducted among six French classes in Spring 2014, will start from this statement: by emphasizing the links between graphemes and phonemes (Saussure, 1916), vocal synthesis may enhance some phonological acquisitions and help the learner better understand the properties of the written language. Indeed, mastering phonems' and graphems' code is necessary, but not enough to enter in the written world (Maisonneuve, 2002). So it may be relevant for young learners to keep a bond between what is about to be written and oral aspects. Consequently, collecting and analysing data that can produce evidence of the impact of this software's audio feedbacks represents an interesting step towards the understanding of how primary school students build writing skills. We will show how we proceeded to get as much evidence as possible of the development of those skills among the students we observed.