Based on the linguistic analysis of game explanations and retellings, the paper's goal is to investigate the relation of preschool children's situated discourse competence and iconic gestures in different communicative genres, focussing on reinforcing and supplementary speech-gesture-combinations. To this end, a method was developed to evaluate discourse competence as a context-sensitive and interactively embedded phenomenon. The so-called GLOBE-model was adapted to assess discourse competence in relation to interactive scaffolding. The findings show clear links between the children's competence and their parents' scaffolding. We suggest this to be evidence of a fine-tuned interactive support system. The results also indicate strong relations between higher discourse competence and increased frequency of iconic gestures. This applies in particular to reinforcing gestures. The results are interpreted as a confirmation that the speech-gesture system undergoes systematic changes during early childhood, and that gesturing becomes more iconic - and thus more communicative - when discourse competence is growing.
Keywords: Discourse competence; iconic gestures; multimodal development.