Content and Language Integrated Learning (CLIL) has emerged as an innovative approach in education, combining content teaching with language learning. This study investigates the impact of authentic materials in CLIL classrooms on students' language proficiency and content knowledge. Using a mixed-methods approach, we analyzed data from various CLIL settings, highlighting the effectiveness of authentic materials in enhancing both language and content acquisition.

Content and Language Integrated Learning (CLIL), authentic materials, language proficiency, content knowledge, student engagement, mixed-methods approach, secondary education, real-world relevance, educational outcomes, curriculum integration.

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