The benefits of learning two languages

• Educational: Achieve L2 without consequences on L1.
• Cognitive: Advanced levels of proficiency and linguistic advantages.
• Social-cultural: Expansion of their world view.
• Economic: Employment opportunities.

Source: Cloud, N., Genesee, F., & Hamayan, E. (2000). The Benefits of Knowing Two Languages. In Dual Language Instruction: A Handbook for Enriched Education (pp. 2-4). Boston: MA: Heinle & Heinle.