A study assessed the performance of language-minority and language-majority children in a two-way Spanish-English bilingual education program in Port Chester, New York. The program treats language learning as a resource for all students, with each group of children teaching their native languages to the other. Second- and third-grade classes are combined. Data on students' Spanish and English reading and oral language skills, mathematics skills in both languages, and perceptions of the classroom environment were gathered for three years. The results were mixed, demonstrating that students can definitely benefit from second language learning in the curriculum but that care should be taken to ensure that native language skills and progress not be compromised. Teacher performance emerged as a crucial variable in the program studied, and careful monitoring of student outcomes in relation to teacher performance is advised. Overall, despite some early problems with student perceptions of difficulty and friction, participant satisfaction was high. (MSE)