Background: Content and Language Integrated Learning (CLIL) is a teaching methodology that integrates learning subject content with acquisition of proficiency in a foreign language (skills), developing both linguistic and conceptual competence. The approach aligns with the recommendations of the National Education Policy (NEP) 2020, which emphasizes the development of bilingual skills and cognitive abilities.

Purpose: The present study explores the efficacy of CLIL in science teaching, with particular emphasis on its influence on content knowledge, cognitive development, and bilingual language acquisition among pre-service teachers.

Method: A quasi-experimental pre- and post-test single-group design was adopted. The study was conducted on 20 pre-service teachers enrolled in the B.Ed. program at Chitkara University. A mixed-method approach was employed, incorporating both quantitative and qualitative data collection and analysis.

Results: Findings indicated that CLIL enhances vocabulary related to subject matter, deepens conceptual understanding through bilingual instruction, and increases student motivation and interest. It also positively impacts problem-solving skills and overall cognitive development, alongside improving language proficiency.

Conclusions: The study concludes that CLIL holds significant potential to enrich science education by fostering both cognitive and linguistic growth. However, challenges such as teacher preparedness and effective assessment strategies remain. The research highlights the need for further investigation into long-term outcomes and teacher training to maximize the educational benefits of CLIL.