The German reality of linguistic diversity and multilingualism as an outcome of internationalization, migration and globalization is finally being acknowledged by the integration, promotion and implementation of multilingualism in German educational institutions. There is however little empirical evidence on the situation of young, multilingual foreign language learners – findings of large scale and several case studies remain inconclusive to allow for a definitive modelling of third language acquisition. This chapter aims at offering insights into two current exploratory case studies of multilingual learners in primary schools and lower secondary level of education in Germany in order to examine the acquisition of English as a tertiary language from a sociocultural point of view. Following a qualitative approach these projects try to illuminate processes of third language acquisition from the learners’ perspective by conducting reconstructive and narrative methods to capture language learning experiences and processes and their interplay with identity construction. In these two exploratory case studies open and age-appropriate interviews were conducted combined with non-verbal procedures. The data was analysed with the use of the documentary method. The here presented cases, which show a maximum contrast with regard to their orientation towards their foreign language classroom, suggest that there is a strong connection between FL acquisition and identity formation and that its quality is determined by the students’ linguistic and cultural identity, their theory of language acquisition, their attitude towards English and other languages and their perception of FL classroom practice.