One of the most misunderstood issues in pre-K-12 education today is how to educate children who are not yet proficient in English. When policymakers refer to these students as English language learners (ELLs)--as many school district officials presently do--or as limited English proficient students (LEPs)--as federal legislators did in the No Child Left Behind Act (NCLB)--it signals the omission of an idea that is critical to the discussion of equity in the teaching of these children. English language learners are in fact "emergent bilinguals". That is, through school and through acquiring English, these children become "bilingual", able to continue to function in their home language as well as in English, their new language and that of school. When officials and educators ignore the bilingualism that these students can and often must develop through schooling in the United States, they perpetuate inequities in the education of these children. The central idea that will emerge from this review of research is that there is a growing dissonance between research on the education of emergent bilinguals and policy enacted to educate them. As the authors will demonstrate, whereas research has consistently shown the importance of building on the children's first language as they develop English language proficiency, U.S. educational policy has often ignored these research findings. In Part I of this review the authors identify the students who are the subject of their attention: students they refer to as emergent bilinguals. In Part II, they briefly review the policies and practices targeted toward this group of students that have developed over the last 40 years. Finally, in Part III, they review what the research reveals about the educational programs, assessments, curriculum, pedagogy, resources, and family and community involvement necessary to educate these children equitably. In Part III, therefore, they also identify and describe the educational inequities that directly affect the education of these children. Most of these inequities stem from policymakers and often educators' lack of understanding of bilingualism itself. Thus, throughout the third part of this review, the authors will discuss how such misunderstandings of the nature of bilingualism have educational equity consequences for some of the most disadvantaged children. The authors end this review with some recommendations. (Contains 9 tables and 39 notes.)