In this paper, we report on a study whose objectives were first to investigate the interaction of children with a multimedia system designed for learning a foreign language and featuring automatic speech recognition functionality. Second, we investigated if, using such a system, users meet some particular difficulties in dealing with the microphone or in solving tasks which implies voice interaction. The study was based on the Italian version of "Tell me More. Kids: The City", a multimedia system dedicated to children aged 8 to 10. The results of the study indicate that, when learners were involved in tasks where they could freely decide if and how many times to use the vocal interaction modality, they did not hesitate to use this modality. The study also revealed the importance of the form of feedback chosen to report the system?s judgment on the learner?s pronunciation to her.