CLIL-SI, Content and Language Integrated Learning in Second Language Acquisition Project (CLILSLA) Research Group, is a collaborative working team formed by primary and secondary school teachers and University lecturers -- specialists on language or content teaching -- that carry out in the classroom research projects about Content Language Integrated Learning (CLIL) programmes, particularly in partial immersion programs or Semi-Immersió (SI) in foreign languages. The aim of the CLIL-SI collaborative research is to improve our understanting of the implications of learning academic contents in multilingual environments, so that it is possible to elaborate and evaluate teaching proposals aimed to achieve a comprehensive linguistic education, integrated and inclusive for the classrooms, for contents as well as languages. CLIL-SI works closely with the consolidated research group GREIP.