Content and Language Integrated Learning (CLIL) is a multifaceted educational approach which has emerged as a major innovation in improving language learning and subject learning in the curriculum. In order to analyse the effect of this approach, a number of studies (Dalton Puffer, C., T. Nikula and U. Smit, eds. 2010. Language Use and Language Learning in CLIL Settings. Amsterdam: John Benjamins; Ruiz de Zarobe, Y. and R.M. Jiménez Catalán, ed. 2009. Content and Language Integrated Learning: Evidence from Research in Europe. Bristol: Multilingual Matters; Ruiz de Zarobe, Sierra, and Gallardo del Puerto. ed. 2011. Content and Foreign Language Integrated Learning: Contributions to Multilingualism in European Contexts. Bern: Peter Lang) have provided a comprehensive compilation of some of the learning outcomes of CLIL settings. The majority of these studies have supported the benefits of the integrative approach in formal contexts; however, there is very little research about the fundamental concept of learning strategies and strategic instruction in CLIL, even though learning strategies are an integral part of the curricular elements that help students to learn. In this paper, we examine whether strategic instruction, centred on reading strategies, can provide the specific techniques that are needed for successful language learning in CLIL settings (Chamot, A.U. 2001. Teaching learning strategies in immersion classrooms [Bridge insert]. The Elementary Immersion Learning Strategies Resource Guide (2nd ed.). http://www.nclrc.org/eils). For our research, we have developed a strategic training programme in reading for students in primary education taught through a Trilingual Education Framework (Basque-Spanish-English) in the Basque Country, Spain. One of our groups received strategic training in reading skills for a period of seven weeks, while the other group did not. Pre-tests and post-tests were carried out for both the control group (no strategic instruction) and the experimental group (strategic instruction). Results indicate that those students who were trained strategically in reading seemed to have greater metacognitive awareness and thus, they obtained better results. However, no significant differences were found between the number and types of strategies used in both groups. Some explanation related to the influence of age and the length of the training procedure will be discussed.