Teaching and learning English in the US are complex processes that are not explained by language theories or methods alone. Concepts such as the relationship between language majority groups and language minority groups, language status, immigration, economics, language planning, and policies add to the complexity of language-learning situations. Effective teachers for the more than 5 million English learners (ELs) in kindergarten through 12th grades require unique knowledge, skills, and dispositions. This article provides a review of the language, learning, and language learning theories and practices for second language teaching, focusing on sociocultural theories and practices.