(a) Each school district that has an enrollment of 20 or more students identified as emergent bilingual (EB) students in any language classification in the same grade level district-wide shall offer a bilingual program as described in subsection (b) of this section for the EB students in prekindergarten through the elementary grades with that language classification. "Elementary grades" shall include prekindergarten through Grade 5; Grade 6 shall be included when clustered with elementary grades.(b) A school district required to provide a bilingual program as described in subsection (a) of this section shall offer dual-language instruction (English and home or partner language) in prekindergarten through the elementary grades, using one of the four bilingual program models described in §89.1210 of this title (relating to Program Content and Design).(c) All EB students for whom a school district is not required to offer a bilingual program shall be provided an English as a second language (ESL) program, regardless of the students' grade levels and home language, and regardless of the number of such students, except in cases where a district exercises the option described in subsection (f) of this section.(d) A school district required to provide an ESL program as described in subsection (c) of this section shall provide an ESL program using one of the two models described in §89.1210 of this title.(e) School districts may join with other school districts to provide bilingual or ESL programs.(f) In addition to the required bilingual programs, school districts are also authorized to establish a bilingual program:(1) if they have an enrollment of fewer than 20 students as described in subsection (a) of this section; and(2) at grade levels in which the bilingual program is not required under subsection (a) of this section.(g) Under the authorization described in subsection (f) of this section, school districts shall adhere to all program requirements as described in §§89.1210 of this title, 89.1227 of this title (relating to Minimum Requirements for Dual Language Immersion Program Models), 89.1228 of this title (relating to Two-Way Dual Language Immersion Program Model Implementation), and 89.1229 of this title (relating to General Standards for Recognition of Dual Language Immersion Program Models).