A discussion of elementary and middle school curriculum design to meet the needs of students learning English as a Second Language (ESL) focuses on the ways in which ESL instruction can be incorporated into the curriculum. It begins with a brief review of statistics on the population of limited-English-proficient (LEP) students in the schools and their educational needs. Several options for organizing programs are described, including transitional bilingual education programs, pull-out ESL instruction, and self-contained ESL classrooms. All are seen as segregating LEP students from their peers. The rationale for "bridge" programs combining ESL with content area instruction is explained and considerations in "bridge" curriculum design are reviewed. Grouping issues are also addressed, including the advantages and disadvantages of homogeneous, heterogeneous, and cooperative learning groups. Computer-assisted instruction is discussed briefly. Finally, one integrated primary school program that has the ESL teacher preparing LEP students for curriculum topics a week in advance of the rest of the class is described. It is concluded that certain strategies are particularly promising for productive mainstreaming, including computer-assisted instruction, bilingual and pull-out programs, the whole language approach to English teaching, and cooperative learning. (MSE)