Picture a high school class that has English language learners (ELLs) from diverse cultural backgrounds with varied academic abilities and language proficiency levels. Now imagine that this class is being taught by a team of two teachers: one content-area teacher (English) and one English as a Second Language (ESL) specialist. Both teachers work together successfully to provide individualized instruction and support their students' language acquisition and content learning. The students are interested and actively involved in the lessons and are making consistent progress in terms of acquiring language proficiency an content knowledge.