Las Americas Middle School is a newcomer program within Houston Independent School District (HISD) that serves students in Grades 4 through 8 who have been in the U.S. for less than one year. As a non-zoned school of choice, Las Americas has no attendance boundary, meaning that students and families must opt to enroll in the school. This brief analyzes how the trajectories of English acquisition vary among Las Americas newcomer students across different subgroups (economic disadvantage, initial English oral proficiency level, grade level upon arrival in HISD, classification as a student with interrupted formal education (SIFE) and refugee/asylee status). It also estimates the causal effects of attending Las Americas on students' English language acquisition.