A discussion of second language learning among language minority students looks at the increasing multiculturalism of the U.S. classroom and a number of related issues, including the relationship between first language development and second language learning, academic language needs, and literacy development, and concern about the appropriateness of standardized testing for linguistically and culturally diverse student populations. It then gives an overview of developments in and principles of integrated language and content (ILC) instruction, or the teaching of content in a second language. Finally, language development is examined in the context of extended school day programs. Basic principles are outlined, and simple strategies for promoting such development through language usage and organization of activities are offered. ILC is seen as a promising technique for additive language development in extended school-day programs because content can be not just academic, but also recreational. Implications for immigrant children in Dutch extended school-day programs are discussed briefly. (Contains 20 references.) A set of strategies and sample activities for ILC instruction in art, music, and physical education, including lesson plans, is presented separately. (MSE)