The choice of an early-exit model may reflect community or parental preference, or it may be the only bilingual program option available in districts with a limited number of bilingual teachers. Late-exit programs differ from early-exit programs "primarily in the amount and duration that English is used for instruction as well as the length of time students are to participate in each program" (Venezky, 1991). Students remain in late-exit programs throughout elementary school and continue to receive 40% or more of their instruction in their first language, even when they have been reclassified as fluent-English-proficient. .
Two-way bilingual programs, also called developmental bilingual programs, group language minority students from a single language background in the same classroom with language majority, English-speaking students. Ideally, there is a nearly 50/50 balance between language minority and language majority students. Instruction is provided in both English and the minority language. In some programs, the languages are used on alternating days. Others may alternate morning and afternoon, or they may divide the use of the two languages by academic subject. Native English speakers and speakers of another language have the opportunity to acquire proficiency in a second language while continuing to develop their native language skills. Students serve as native-speaker role models for their peers. Two-way bilingual classes may be taught by a single teacher who is proficient in both languages or by two teachers, one of whom is bilingual. .
ESL Program Models, rather than bilingual programs, are likely to be used in districts where the language minority population is very diverse and represents many different languages. ESL programs can accommodate students from different language backgrounds in the same class, and teachers do not need to be proficient in the home language of their students.