This paper examines the content-language integrated (CLI) second language (L2) education offered by the CCUEI Research Collaborative in China. It explores how CCUEI-developed curriculum reflects the theoretical foundations of an immersion experiment and how the research-based theoretical foundations of CLI L2 have been applied in practice. It presents best practices for L2 instruction that have emerged supporting the notions that content-area classes provide natural environments for L2 education and content-based language teaching motivates English language learners. (Contains 4 notes.)