This study explores how Contextualized Language Immersion (CLI) can enhance the comprehension and practical application of advanced biology concepts among English as a Foreign Language (EFL) students.

The research aims to answer the following questions: 

1. Does CLI lead to a significant improvement in EFL students' understanding of advanced biology concepts when compared to traditional teaching methods? 

2. In what ways does CLI affect students' engagement, motivation, and confidence in learning biology in a language that is not their native tongue?

3. What qualitative insights do students provide about the effectiveness of CLI in bridging the linguistic and conceptual gaps present in science education?

This study is based on the Content and Language Integrated Learning (CLIL) framework, which encourages the simultaneous acquisition of subject content and a foreign language. CLIL is commonly used in European and international educational systems to assist bilingual and multilingual students in gaining subject-specific knowledge. It aligns with sociocultural learning theories, especially Vygotsky’s Zone of Proximal Development (ZPD), which suggests that learners grasp knowledge more effectively through guided, contextual interactions.   Additionally, CLIL incorporates Cognitive Load Theory (Sweller, 1994), indicating that minimizing unnecessary cognitive load through clearer explanations and vocabulary support improves understanding. The study also reflects Constructivist Learning Theories (Piaget, 1950), highlighting that knowledge is best constructed in interactive and contextualized environments.   Given its relevance in Europe and beyond, this research aligns with policy initiatives like the European Commission’s Framework for Multilingual Education, which advocates for integrated content-language strategies to ensure equitable access to STEM education for various linguistic groups. The findings contribute to ongoing conversations in international education research regarding effective methods for addressing language barriers in science education, thus informing global best practices in bilingual teaching.

This study utilizes a quasi-experimental design to compare the effectiveness of CLI-based instruction with traditional teaching methods. A total of 32 advanced EFL biology students were randomly divided into two groups: • Experimental Group (n=16): Received instruction based on CLI. • Control Group (n=16): Received traditional lecture-based instruction. The intervention spanned 12 weeks and featured scaffolded, language-rich environments using contextualized biology materials. Data Collection Instruments 1. Pre- and Post-Surveys: • A Quantitative Knowledge Test focused on genetics concepts to evaluate comprehension gains. • A Likert-scale engagement survey to measure student motivation and their perceived learning experience. • Open-ended qualitative responses to gather detailed student perceptions. 2. Instructional Treatment: • The CLI treatment involved real-world applications, structured vocabulary exercises, simplified explanations, and immersive learning activities. Data Analysis • Statistical Tests: Paired and independent t-tests will be used to assess the gains in comprehension and application both within groups and between groups. ANOVA (Analysis of Variance) will help measure the differences in engagement across various types of interventions. • Qualitative Data Analysis: Thematic coding will be employed to uncover recurring themes in student feedback regarding the impact of CLI.

Preliminary findings indicate that the CLI group showed significantly greater improvements in biology literacy, conceptual understanding, and engagement compared to the control group. Statistical analysis showed: * Enhanced knowledge gains in genetics concepts within the CLI group. • Better engagement scores, reflecting increased motivation and confidence in learning. • A decrease in language-related learning barriers, supporting the effectiveness of CLIL strategies. Qualitative data analysis revealed that contextualized scenarios boosted students’ motivation and confidence, enabling them to tackle complex biological concepts more effectively. Participants noted that CLI: 1. Closed the gap between language and content learning by making biology concepts easier to grasp. 2. Encouraged active engagement and critical thinking, rather than passive learning. 3. Alleviated anxiety and increased participation, as students felt more supported in a structured, immersive environment. These findings underscore the importance of CLIL and CLI methodologies as scalable solutions for linguistically diverse science education. Given its alignment with global education policies, the study adds to the international conversation on multilingual STEM instruction, advocating for wider adoption in bilingual learning settings.

Coyle, D., Hood, P., & Marsh, D. (2010). CLIL: Content and Language Integrated Learning. Cambridge University Press. Sweller, J. (1994). Cognitive Load Theory, Learning Difficulty, and Instructional Design. Learning and Instruction, 4(4), 295-312. Vygotsky, L. S. (1978). Mind in Society: The Development of Higher Psychological Processes. Harvard University Press. European Commission (2019). Language Teaching and Learning in Multilingual Classrooms: Framework for Content and Language Integrated Learning (CLIL).