Several recent studies have demonstrated how critical prosody is in a didactic context. Some of them focused on how accent affects syllables or words on which the teacher wants to draw pupil’s attention (Fox 2001). Others focused on the nature and role of pauses in the teacher’s speech (Candea 2000). Finally, other studies focused on prosody as a special vector for emotions (Whitehead et al 2000), or on expressiveness and dramatization as a key to improve understanding of the text in the reading process (Hudson et al 2005). Every teaching sequence involves the teacher and the pupils at different levels of activity. These levels are prosodicaly determined by the nature of the subject which is taught and are analysed by the pupil in two different ways : - from a verbal point of view : the function of prosody is referential (focus, hierachization, segmentation of the speech). - from a non verbal point of view (gestural complex) ; the function of prosody is attitudinal and emotional. Our assumption is based on a perceptual point of view : the hypothesis is that these levels of activity may be determined by specific prosodic strategies which are independent from the nature of the subject which is taught, but which vary according to the nature of the mental task that the teacher wants to ask for, or that the pupil wants to accomplish. The corpus is about two 3 year-old children in kindergarden and 3 microsystems about learning the lexicon: nominal, verbal and grammatical lexicon (1227 occurrences). The data is recorded, written down and analysed by Praat (audio software), which give audio informations and pictures of all parameters of prosody. The study of prosody in a microgenetic perspective suggests that prosodic strategies vary according to the nature of the linguistic and mental task that the speaker shows he is willing to accomplish. We observe that, when the centring of one the speaker is on the speech (conversational activity), the function of prosody may be referential, attitudinal or emotional. But when the centring of the speaker focuses on a new notional content, the verbal production implements an implicit categorisation of the situation and the prosody indicate a focus on the specific task to accomplish i.e. a focus on the mental product of the speech / activity (here construction of lexical and conceptual competences). The pictures show a flat fundamental frequency, but this is offset by intensity variations when it is heard ; the speaker’s centring then focuses on the content of the message, which is linked to the cognitive task to be accomplished. The instrumental analysis shows that this strategy is used irrespective of the length of the intervention. However, the longer the utterance is, the more focused the non variation segment is. We observe this trend whatever the nature of the school task and whatever the learning. Analysis: Teaching/ learning situations is based upon prosody which acts as a contextual guidance in the cognitive treatment of the information following two axes: (1) the perceptive scanning of specific prosodic entities and their interpretation when heard, (2) the production of specific prosodic entities.

The corpus is about two 3 year-old children in kindergarden and 3 microsystems about learning the lexicon: nominal, verbal and grammatical lexicon (1227 occurrences). The data is recorded, written down and analysed by Praat (audio software), which give audio informations and pictures of all parameters of prosody.

Prosody is hence an essential part of the intersubjectivity structuring for it is a manifestation of what, in a speaker’s speech, depends upon the other’s speech: what is being said does not reflect the speaker’s intention, but the way it is said is considered a “counterword” (Bakhtine 1978). Thus, the representations are not only an actualization of a possibility of inference, but, on the contrary, movements through which the participants position themselves in the speech space. From a more general point of view, prosody would be a fundamental resource to perceive the context and to determine, at the perceptual level, frameworks allowing to indicate the pupil the mental task to be achieved.