This article contains a description of the Dual Proficiency (DP) program in an urban elementary school located in the heart of a large south-western city, as well as the teachers who designed and now implement DP, and the immigrant community participating by choice in DP. We write from a context where, ironically, the number of English language learners (ELL) in the United States is at its highest and yet use of the children's native language for classroom instruction is severely restricted, for all intents and purposes, by law. On top of this, district, state and national accountability demands, and the resulting focus on standardised test scores as indices of achievement, have served to narrow the curriculum and to direct classroom time to intensively tested skills. For schools with large numbers of students whose scores do not meet state testing standards, the prescribed remedy is often mandated, skills-based commercial programs. In the DP program, on the other hand, thoughtful content-based instruction utilising academic language connections between the students' two dominant languages (Spanish and English) with explicit recognition of the contributions of additional heritage indigenous languages from Mexico and Central America provides the scaffold to academic understanding for participating students. DP students consistently score significantly above their non-DP peers on state-mandated achievement tests. (Contains 1 table and 2 footnotes.)