Numerous studies have shown that interaction greatly facilitates language acquisition by providing learners with opportunities for feedback, comprehensible output and comprehensible input (see Mackey, 2007, 2012 for a review). The benefits of interaction have been widely shown among adults and also among children learning English as a second language (ESL) in English speaking communities. Accordingly, interactive tasks have become commonplace in ESL lessons. However, the value of interaction has not been sufficiently tested with young children who learn English as a foreign language (EFL), and studies are even scarcer with children in a new learning context that is becoming prevalent in Europe: content and language integrated learning (CLIL). In order to fill this research niche, the aim of the present study is to provide a detailed description of the conversational interactions of 20 Spanish learners of English as a foreign language (age 11) while resolving a picture placement task in pairs in a CLIL school in Spain. Our analysis of their conversational interactions focused on their ability to resolve the task autonomously as well as on their ability to use interactional strategies in order to reach mutual understanding. Following previous studies, our analysis includes conversational adjustments, repetitions, L1 use and provision of feedback. The results show that, although less frequently than adults and ESL children from previous studies, the learners made wide use of negotiation strategies and successfully understood each other throughout the task. Also, we found that the learners used different and creative linguistic strategies when facing lexical gaps and only resorted to L1 terms rarely. However, some limitations were also reported. The learners were unable to provide feedback to each other and structural transfer from Spanish was very common and resulted in abundant errors. As these transfer errors did not cause communication breakdowns among the participants, they were also unable to notice them and repeatedly communicated with utterances that would be unintelligible or difficult to interpret by native learners.In light of the results we suggest that, while interactive activities seem to have provided our learners with great opportunities to use the target language in a meaningful way, it is necessary to understand their limitations when learners share the L1 before they make their way into EFL classrooms.