ore and more students in today’s secondary subject matter classrooms in America are bilingual ELLs (English language learners), a fast-growing student population in the U.S. public schools (National Center for Education Statistics, 2019). In New York City, about 50% of the total public-school students speak a language other than English at home and one out of every six secondary school students are an ELL (New York City Department of Education, 2019). Those ELLs are served by the three language programs: TBE (Transitional Bilingual Education program, mostly for middle and high school students), DL (Dual Language Program, mostly for elementary and middle school students), ENL (English as a new language program, formerly ESL, for almost all ELLs). In this article, I focus on bilingual subject matter instruction for high school students in the TBE program. Every day, the secondary ELLs in the TBE program attend subject matter classes taught by bilingual subject matter teachers using the bilingual education pedagogy. According to the guidelines shown on the website of New York City Department of Education