The document discusses content-based language teaching (CLIL) in the classroom. It defines CLIL as teaching content through the target language to promote meaningful communication. The advantages include creating contexts for use of the target language, easier recall of content-based information, and development of cognitive and communication skills. Challenges include teachers lacking subject knowledge and difficulty assessing student performance. Effective planning involves setting objectives, adapting content and language, using tasks, and criteria for evaluation. CLIL is a useful strategy that emphasizes content learning through communication in the target language.