This paper presents the results of an experience with “VocalizaL2”, an application for Second Language (L2) learning of Spanish, in a multilingual environment at the Vienna International School (VIS). For the experiment, a group of 6th-graders at the school practiced with the application during 5 sessions altogether with their regular classes. The results of the experiment show on one hand, the great motivation power that computer-based L2 tools have for the pronunciation training of young learners, while also resulting useful for the teachers. On the technical aspect, the tool and the algorithms within are described and a preliminary analysis points out their ability to correct and motivate non-native Spanish pronunciation.